COMPUTERS

Computer Fundamentals & Photoshop

Syllabus:-

UNIT-I:

Introduction to computers, characteristics and limitations of computer, Block diagram of computer, types of computers, uses of computers, computer generations. Number systems :binary, hexa and octal numbering system

UNIT-II:

Input and output devices: Keyboard and mouse, inputting data in other ways, Types of Software: system software, Application software, commercial, open source, domain and free ware software, Memories: primary, secondary and cache memory. Windows basics: desktop, start menu, icons.

Unit –III

Introduction to Adobe Photoshop, Getting started with Photoshop, creating and saving a document in photoshop, page layout and back ground, photoshop program window-title bar,menu bar,option bar, image window, image title bar,status bar,ruler,paletts,tool box, screen modes,saving files,reverting files,closing files.

Unit –IV

Images: working with images, image size and resolution, image editing, color modes and adjustments, Zooming & Panning an Image,, , Rulers, Guides & Grids- Cropping & Straightening an Image, image backgrounds ,making selections.

Working with tool box: working with pen tool, save and load selection-working with erasers-working with text and brushes-Color manipulations: color modes- Levels – Curves - Seeing Color accurately - Patch tool – Cropping-Reading your palettes - Dust and scratches- Advanced Retouching- smoothing skin

Unit-V

Layers: Working with layers- layer styles- opacity-adjustment layers

Filters: The filter menu, Working with filters- Editing your photo shoot, presentation –how to create adds ,artstic filter,blur filter,brush store filter, distort filters,noice filters,pixelate filters, light effects,difference clouds,sharpen filters,printing.

UNIT-I

Introduction to computers

Definition of Computer:-

Ø A computer, in simple terms, can be defined as an electronic device that is designed to accept data.

Ø To perform the required mathematical and logical operations at high speed, and output the result.

1) Characteristics of computer:-

Ø We have seen that a computer is an electronic device that performs a function based on a given set of instructions known as a program.

Ø A computer accepts data, processes it, and produces information.

ddiagram

Ø The important characteristics of a computer are discussed in the following text.

d diagram

Speed:-

Ø Computers can perform millions of operations per second, which means that data may otherwise take many hours to process is output as information in the blink of an eye.

The speed of computers is usually given in nano seconds and pico seconds where 1 nano second=1*10 9 seconds and 1 pico seconds=1*10 12 seconds.

Accuracy:-

Ø A computer is a very fast reliable and robust electronic device. It always gives accurate results, provided the correct data and set of instructions are input to it.

Ø Hence in the event of an error, only the user who has fed the incorrect data/program needs to held responsible.

Ø This clearly means that the output generated by a computer depends on the given instructions and input data.

Ø If the input data is wrong then the output will also be erroneous.

Ø In computer terminology this is known as garbage-in, garbage out(GIGO).

Automation:-

Ø Besides being very fast and accurate, computers are automatable devices that can perform a task without any user intervention.

Ø The user just needs to assign the task to devices attached to it and executes the program instructions.

Diligence:-

Ø Unlike humans, computers never get tried of a repetitive task.

Ø It can continually work for hours without creating errors.

Ø Even if a large number of executions are needed each and every execution requires the same duration and is executed with the same accuracy.

Versatile:-

Ø Versatility is the quality of being flexible today computers are used in our daily life in different fields.

Ex:- Banking, Personal Laptop, Railways, Teaching.

Memory:-

Ø Similar to humans, computers also have memory.

Ø The computer stores a large amount of data and programs in the secondary storage space.

Ø The stored data and programs can be retrieved and used whenever required.

Ø Secondary memory is the key for data storage.

Ex:- Floppy Disks, Optical Disks, (CDs and DVDs), Hard Disks Drivers.

No IQ:-

Ø Although the trend today is to make computers intelligent by inducing artificial intelligence (AI) in them.

Ø They still do not have any decision- making abilities of their own.

Ø Thus, their IQ level is Zero. They need guidance to perform various tasks.

Economical:-

Ø Today, computers are considered as short term investments for achieving long term gains.

Ø Using computers also reduces manpower requirements and leads to an elegant and efficient way of performing various task.

Ø Hence computers save time, energy, and money, when compared to other systems computers can do work in lesser time.

Limitations of computer:-

Ø A computer is a versatile device yet it has some limitations the limitations are given here.

No thinking power:-

Ø A computer cannot think on its own. A human being, on the other hand can think rationally.

Ø A computer performs whatever jobs assigned to it.

No creativity:-

Ø A computer cannot sing like mange war, it cannot paint or dance. It cannot act like amitabh bhachan. While a human being has some type of creativity, a computer has not creativity on its own.

Initial cost:-

Ø The cost of installation and maintenance of computers is again a problem. small firms cannot afford for the maintenance of computers in labs.

Ø Likewise the human being are also to be trained to learn a lot of programming languages and packages in order to operate the computer.

Not portable:-

Ø Certain types of programmers are not suitable for using on the other type of computers.

Ø The operating system does not support for it.

Virus problems:-

Ø Computers are liable to get viruses. The viruses are created by computer hackers in order to infect the computers.

Ø These viruses are highly dangerous to computers. Data may be lost or there is damage to the system.

2) Block Diagram of Computer:-

Ø A computer is an electronic device that basically performs five major operations.

§ Accepting data or instructions (input)

§ Storing data

§ Processing data

§ Displaying results

§ Controlling and coordinating all operations inside a computer.

Ø Which shows the interaction between the different units of a computer system.

diagram

Input:-

Ø This is the process of entering data and instructions (also known as programs) in to the computer systems.

Ø They data and instructions can be entered by using different input devices such as keyboard, mouse, scanner, and track ball.

Ø So it is the responsibility of the input device to convert the input data into binary codes.

Storage:-

Ø It is the process of saving data and instructions permanently in the computer so that they can be used for processing.

Ø The computer storage space not only stores the data and programs that operate on that data also storage the intermediate results and the final results of processing.

Output:-

Ø Output is the process of giving the result of data processing to the outside world (external to the computer system).

Ø The results are given through output devices such as monitor and printer.

Ø Since the computer accepts data only in the binary form and the result of processing is also in the binary form.

Ø The output devices, therefore convert the results available in the binary codes into a human readable language before displaying it to the user.

Control unit;-

Ø It is just like the nervous system of the body. this part will decide which data is to send first, how to send etc.

Ø Accordingly, it will coordinate the input, output storage devices. The control unit has the following functions.

à It sends instructions to other parts.

à It sends commands to logical unit.

à If facilitates the data flow to be systematic between memory and logical unit.

à It paves the way for sending the processed information to output or storage devices.

Memory unit:-

Ø The computer will send the data from alu to memory.here memory means data storage system. In case of human being he will store the data in the brain.

Ø If he feels that he may forget some data or details, he will write that data in his note book or diary.

Ø It is called the permanent or secondary storage memory in computer technology.

Two types of memory:-

Ø As already mentioned this memory is of two types

à Primary memory (main memory) and

à Secondary memory

Primary memory:-

Ø This primary memory is again divided into many small parts. These small parts are called memory cells.

Ø The computer will fill-up the information given by the users in these cells.

RAM AND ROM:-

Ø The primary memory in the computer is divided into two parts

à Random access memory (RAM)

à Read only memory (ROM)

Random access memory:-

Ø When we open the computer, some system start up (booting) process begins. These contents are written in memory at the time of manufacture and they cannot be changed by the user.

Ø This type of memory is called ROM this information is not lost even though the computer is switched off as it is not lost it is called non volatile memory.

PROM and EPROM:-

Prom:-

Ø As the name indicates this type of memory can be written only once by the user or programmer, there after it can not be changed by the user.

Eprom:-

Ø In this type of memory, we can modify the contents of prom as many times as we want this type of memory can be modified using ultraviolet light.

RAM (Random Access Memory):--

Ø This type of memory can be read and written by the user. It is called ram because any place on a chip can be selected at random and used to store programs or data.

Ø It deals with current information that we are working presently.

Secondary memory:-

Ø In order to store the information permanently in the computer secondary memory is the solution.

Ø The information so stored in the secondary memory is called saving of information the computer in this case will ask for the file name.

Ø Once the files are saved the computer will reproduce it as and when demanded we can make changes in that file.

Ø There will be no loss of information even when the computer is struck off or power goes off, normally secondary memory is stored in floppy disc, hard disc or cd rom.

Storing devices in computer:-

Ø The storing devices In the computer are called disk drives. They are mainly of three types.

diagram

Hard disk:-

Ø A hard disk is used to store/retrieve the data or information. A hard disk is permanently kept in the computer at the time of purchase.

Ø The storing capacity of hard disk is higher than any other storing disk devices. Now days the storing capacity of hard disk is 80 to 160 gb and even more.

Floppy disk:-

Ø A floppy disk is a device used to record and take the information from the computer to else where. We can also see the information and programs.

Ø If we do not need the information stored in floppy. we can delete the unwanted information and store some other information in its place.

Compact disk:

Ø The instrument that is useful in this connection is called compact disk. It can store the information from 400 to 700 mb.

Ø Many latest programs are available only on these compact disks we can directly operate some programs only from the compact disc.

3) Types of Computers:-

Ø The computers have been classified into various types depending upon size, use and input .

diagram

Digital computer:-

Ø Digital means relating to numbers. Here we will give a combination of numbers, figures, symbols, words as input.

Ø These types of computers are mainly used in educated related matters. As the size of these computers is very small, they will be inserted into watches and pocket size calculators.

Hybrid computer:-

Ø These are the computers which have the features of both analog and digital computers.

Ø If we give the input in the form of analog and digital calculations then it is called hybrid computer.

ON THE BASIS OF USE OF COMPUTERS:-

Ø On the basis of use of computers, we can classify them in the following way.

Special purpose computer:-

Ø Special purpose computers, as the name suggests, have been made keeping in mind. The special objectives and conditions of the institutions or environment.

Ø These computers are not useful for general purpose.

General purpose computer:-

Ø These are used in day to day works, as these are general computers, we can use them for word processing, calculations etc.

On the basis of size and working principle:-

Ø The computers can be classified in the following way. On the basis of size and working capacity in the following way.

Micro computer:-

Ø As micro processor is used in these types of computers, they are called micro computers. These are also called personal computers.

Ø The examples for micro computers are Pentium III, Pentium iv.

Characteristics of micro computers:-

à They are the smallest and cheapest computers.

à Only one person can use the system at a time.

à Only one central processor is used in these type of computers.

à The storage capacity and processing speed are small.

Mini computers:-

Ø These computers are slightly bigger than micro computers. These are used for small business needs. They are multi-user systems.

Ø Many people can work on the systems at the same time we can have time sharing method in this computer.

Features of mini computers:-

Ø Cpu speed - high

Ø Storage capacity - above 1000 gb

Ø Areas of application – engineering, scientific research and graphic design.

Ø Examples - hp 2000 model

Main frame computer:-

Ø If you want to calculate millions of calculations, mainframe computers are used as this computer is having time sharing method.

Ø A number of processors are used in these computers everyone is given some time to do calculations. These computers will occupy a lot of space in the premises.

Features of mainframe computers:-

Ø Cpu speed - high

Ø Storage capacity – 5200 gb

Ø Areas of application - banks, insurance, railways, govt organizations

Ø Examples - ibm series, hp 9000 model.

Super computers:-

Ø These are the super fastest computers in the world. The high speed in these computers is possible because of a number of processors used in them.

Ø It shares the one time instead of one single process at one time it shares the information with hundreds of computers.

Ø These type of computers are mainly used in space research and weather forecasting.

Features of super computers:-

Ø Cpu speed - very high

Ø Storage capacity - large capacity

Ø Areas of application - space, defence research weather forecasting.

Ø Example - param -10,000.

4) Generations of Computers:-

Ø Therefore, each generation of computers is characterized by a major technological development that has drastically changed the way in which computers operate.

Ø Consequently these computing devices have become smaller, cheaper, powerful, efficient, and more reliable.

First Generation (1940-1956):- Vacuum Tubes

Ø First Generation computers used a very large number of vacuum tubes for circuitry and magnetic drums for memory.

Ø These computers were so big in size that they often required an entire room to be installed.

Ø The first generation computer were very expensive and were hence mainly used for scientific purposes.

Advantages:- They were the fastest calculating devices of their time.

Disadvantages:-

Ø They generated a lot of heat

Ø They consumed a lot of electricity

Ø They computers had limited commercial use because they were difficult to program

Ø They were very expensive.

Second Generation (1956-1963):- Transistors

Ø Second generation computers were manufactured using transistors rather than vacuum tubes.

Ø Transistors were invented in 1947 but were used for manufacturing computers only in the late 1950’s.

Ø Transistors were far superior to vacuum tubes.

Ø Computers manufactured using transistors were smaller, faster, cheaper, and more energy- efficient and reliable than their first generation predecessors.

Advantages:-

Ø They consumed less electricity and thus generated less heat as compared to the first generation computers.

Disadvantage:-

Ø Second generation computers were manufactured using transistors which had to be assembled manually.

Ø This made commercial production of computers difficult and expensive.

Third Generation (1964-1971):- Integrated Circuits

Ø Integrated chips were smaller, less expensive, more reliable and faster in operation, consumed less power, and generated less heat than the components used earlier.

Advantages:-

Ø They were faster than second generation computers and could perform one million transactions per second.

Ø These computers had faster and larger primary memory and secondary storage.

Ø Third generation computers were widely used for scientific as well as business applications.

Ø Third generation computers could run time sharing operating systems, which allowed interactive use of a computer.

Ø By one or more users simultaneously, thereby improving the productivity of the users.

Disadvantages:-

Ø These computers were difficult to maintain

Ø They got heated very quickly.

Fourth Generation (1971-1989):- Microprocessors

Ø The microprocessors launched the fourth generation of computers with thousands of integrated circuits built onto a “single silicon chip”.

Advantages:-

Ø These computers were smaller, cheaper, faster, and more reliable than their predecessors.

Ø They consumed less electricity and generated less heat.

Ø They had faster and larger primary memory and secondary storage.

Ø They could be used as general-purpose computers.

Ø GUIs enabled people to learn to work with computers very easily. Hence the use of computers both in offices and a homes became wide spread.

Ø Networks allowed sharing of resources, thereby enabling efficient utilization of computer hardware and software.

Disadvantage:- They were not intelligent systems.

Fifth Generation (Present and Beyond):- Artificial intelligence

Ø Fifth generation computers are completely based on the new concept of artificial intelligence.

Ø Although such computers are still in development, there are certain applications such as voice recognition that are widely being used today.

Gaming:-

Ø Computers are programmed to play games such as chess and checkers.

Expert Systems:-

Ø Computers are programmed to take decisions in real-world situations.

Natural Languages:-

Ø Computers are programmed to understand and respond to natural human languages.

Neural Networks;-

Ø Systems are programmed to simulate intelligence by reproducing the physical connections that take place in animal brains.

Robotics:-

Ø In Robotics computers are widely used in manufacturing and assembly plants for performing certain tasks.

Ø However, the tasks that robots can perform are limited they find it difficult to identify objects based on appearance or feel, and they still move and handle objects clumsily.

5) Number systems:-

Binary Number System:-

Ø With binary number all the columns are power of 2 note that in the table all the columns are specified

In power of 2.

Ø So in order to convert a binary number into its decimal equivalent multiply that place holder amount

(Power of 2) by the digit, and then add them all up.

diagram

For example:- let us convert 1101 into decimal

Decimal number = 1*2³ + 1*2² + 0*2¹ + 1*2⁰

= 1*8 + 1*4 + 0*2 + 1*1

= 8 + 4 + 0 + 1

= 13

Adding two binary numbers:-

Ø Adding binary numbers is not only simple but also similar to the addition of decimal numbers.

Ø While performing binary addition, start by adding the bits (digits) in one column, or place weight, at a time, from right to left as we do in case of adding decimal numbers.

Ø However, to perform binary addition you must memorize the rules of addition.

Rules of Binary Addition :-

diagram

Subtracting Two Binary Numbers :-

Ø Now that you have learnt to perform addition on two binary numbers, subtraction will also be an easy task to perform. Like binary addition, there are certain rules to be followed for binary subtraction.

Ø These rules can be summarized as:

0 - 0 = 0

1 - 0 = 1

1 - 1 = 0

0 - 1 = 1, and borrow 1 from the next more significant bit

diagram

MULTIPLYING TWO BINARY NUMBERS:-

Ø Two numbers A and B are multiplied using partial products. For each digit in B, the product of that digit in A is calculated and written on a new line (shifted leftward).

Ø The partial products are added together to get the final result.

The rules of multiplications of binary numbers are same as that of decimal numbers, that is

0 x 0 = 0
0 x 1 = 0
1 x 0 = 0
1 x 1 = 1

diagram

Division of Two Binary Numbers:-

Ø Binary division is again similar to dividing two decimal numbers.

Ø According to the long division method, the divisor is multiplied with quotient and the result is then subtracted from the dividend.

diagram

OCTAL NUMBER SYSTEM :-

Ø The octal numeral system, is the base-8 number system, and uses the digits 0 to 7.

Ø This number system was used extensively in early mainframe computer systems, but has become less popular when compared with binary and hexadecimal number systems.

Ø In order to convert an octal number into its decimal equivalent, multiply that place holder amount (power of 8) by the digit, and then add them all up.

For example:- let us convert (123)₈ into decimal

Now, use the above table to form the decimal number.

Decimal number = 1*8² + 2*8¹ + 3*8⁰

= 1*64 + 2*8 + 3*1

= 64 + 16 + 3

= 83

HEXADECIMALNUMBER SYSTEM:-

• The hexadecimal numeral system is the base-16 number system.

• It uses sixteen distinct symbols- the symbols 0–9 to represent values zero to nine, and A, B, C, D, E, F

(or a to f) to represent values ten to fifteen.

• The main problem with binary numbers is that for larger values, binary numbers quickly become too unwieldy. The hexadecimal (base 16) number system overcomes this problem as hex numbers are very compact.

• It is very easy to convert from hex to binary and binary to hexadecimal.

• In hexadecimal, just like in the binary, octal and decimal number systems, we start counting in the first column which represents the smallest unit, ones. Then, working from right to left, we move to a 16s column; a 256s column; a 4096s column; a 65,536s column; and so forth.

diagram

Convert Hexadecimal Number into Binary:-

Ø Break the binary number into 4-bit groups beginning with the LSB and substitute the corresponding four bits in binary for each hexadecimal digit in the number.

For example, convert OxABCD into its binary equivalent.

(ABCD)₁₆ = (1010 1011 1100 1101)₂

UNIT-II

Input and output devices:-

Ø The various input devices are given below.

Keyboard:-

Ø As explained earlier, we type commands from keyboard just like the type writer. There are, however, more key buttons on computer keyboard than in a type writer.

Some of important buttons:-

Ø Let us discuss some important buttons of key board

Function buttons:-

Ø These buttons appear in the front of the keyboard starting from f1 to f12.each one has a specific function to perform in computer working.

Ø The functions of these keys are changed according to the package selected by the user.

diagram

Cursor control keys:-

Ø In order to move the cursor from top to bottom, and back to front, control keys are useful. There are four buttons having arrows according to which they will move.

diagram

Special keys:-

Ø In addition to above keys, we have some special key buttons.

Shift keys:-

Ø This keys is used to get special numbers or signs printed on upper part of buttons and to perform other functions.

Control and alter keys:-

Ø These keys will work depending upon the computer language or package used.

Caps lock:-

Ø When you press this key, a green light appears on the right side of keyboard. This key is used to type capital letters.

Num lock:-

Ø This key is useful in entering numerical data.

Esc key:-

Ø This key is used to stop the work in the middle of program or to move to the proceeding operation.

Delete key:-

Ø This key is used to delete the letters from the cursor place to its right side.

Mouse:-

Ø A mouse is an input device that is used to point at objects on the screen by moving it on a small, hard surface.

Advantages	Disadvantages
Easy to use	It is not suitable for all occasions
It is fast	We can not get pointing device for all commands

Track ball:-

Ø The track ball works just like a mouse except the ball is on the top. The finger movements of our hand makes movements of the pointer on the screen.

Ø This is useful particularly in games. When we are playing games, we can control the cursor movements by rotating the ball with hands.

Advantages	Disadvantages
Same as above mouse	Limited use
Mainly used in portable computer where there is less space formouse	Not easy to handle mouse

Keyboard:-

Ø A keyboard is an instrument similar to a type writer which is used to type commands and data in to a computer.

Alphanumeric keys:-

Ø These are used to type letters and numbers (the letters A-Z, a-z and the digits 0-9).

Punctuation keys:-

Ø These are used to type punctuation marks like comma and period.

Function keys:-

Ø These keys do not have a fixed function. They perform some activity as directed by the software that is running on the computer at that time.

Scanners:-

Ø A scanner is another type of input device which is used to read the documents.images,graphs,

Photographs and any other information.

Ø A scanner scans an image and transforms the image to a form that can be used on a computer.

Ø You can save the scanned image in the form of a file, edit it and then print it.

Types of scanners:-

Ø They are two types of scanners

v Roller feed scanner

v Flatbed scanner

Roller feed scanner:-

Ø The paper bearing the image is passed over a roller where it Is captured.

Flat bed scanner:-

Ø Works like a photocopier, it can scan and store images from books without having to remove the page, which is difficult in the case of the foller-feed scanner.

Touch screen:-

Ø When the finger touches on any object on the screen, that object registers the input. A touch screen serves as an efficient input device.

Ø The sense that even a layman can operate the computer with the help of his finger.

Light pen:-

Ø It appears like a pen with a small light on its end, when the pen touches a particular point on the screen, it registers the input.

Advantages	Disadvantages
Easy to operate	Use is limited
No need for typing	Separate monitor is required

Output devices:-

Monitor:-

Ø It appears like a T.v screen.

Ø It is made of cathode ray tube (crt).

Ø It has both black and white types.

Ø It has different sizes like 14,15,17,19 and 21 inches.

Ø Now a days people are using flat type monitors.

Printer:-

Ø We can also get the output of our information on a printer attached to the computer.

Types of printer:-

Ø These are mainly three types of printers in practice.

diagram (3)

Dot matrix printers:-

Ø These printers print the letters by pressing the inked rubber on paper. It prints dots wise.

They are used in ordinary office uses.

Characteristics of dot matrix printers:-

Ø These printers print the matter line by line.

Ø As they are printing dots wise, the quality is not so good.

Ø They are cheap but make noise while printing.

Ø They are slow in printing and take a lot of time.

Ø They print only in black and white letters.

Inkjet printers:-

Ø These printers give prints in multi color. These printers spread ink on the paper. These printers print the pages step by step.

Ø these are used mainly when we need colorful posters brouchers etc.

laser printers:-

Ø it is mainly used in DTP needs, these printers are costly but they give fine quality prints. Unlike dot matrix printers, it prints the whole page at a time.

Speakers:-

Ø Speakers generate sounds from the computer, now a day’s all the users are using speakers having capacities like 100 watts, 250 watts, 550 watts etc.

Ø Since the multimedia facilities have improved a lot, almost all the people are using modern speakers.

Floppy, cd, hard disks: -

Ø These devices serve both as input as well as output devices as they are giving information just like a printer.

Ø We can treat them as output devices also. We have already discussed about them to previous lessons.

2) Types of software:-

Definition of Software:-

Ø The computer hardware cannot think and make decisions on its own. So, it cannot be used to analyze a given set of data and find a solution on its own.

Ø The hardware needs a software (a set of programs) to instruct what has to be done.

Ø A program is a set of instructions that is arranged in a sequence to guide a computer to find a solution for the given problem.

Ø The process of writing a program is called programming.

Ø Computer software is written by computer programmers using a programming language.

Examples of computer software include:-

• Computer Games

• Driver Software

• Educational software

• Media Players and Media Development Software

• Productivity Software such as word processors, database management utilities, and presentation software, Operating Systems software, etc.

diagram

Commercial Software:-

Ø Commercial software is any software or program that is designed and developed for licensing or sale to end users or that serves a commercial purpose.

Ø Commercial software was once considered to be proprietary software, but now a number of free and open source software applications are licensed or sold to end users.

Ø Off the shelf software programs, such as games or those in computer specialty stores and grocery stores.

Ø Some examples of commercial software

§ Microsoft products such as the windows operating system and MS office are some of the most well known examples of commercial software.

Open source software:-

Ø Open source is software is software whose source code is available for modification or enhancement by anyone.

Ø “source code” is the part of software that most computer users don’t ever see.

Ø It’s the code computer programmers can manipulate to change how a piece of software-“ a program” or “ application”- works.

Ø Programmers who have access to a computer program’s source code can improve that program by adding features to it or fixing parts that don’t always work correctly.

Domain and Free Software:-

Ø Software that has been placed in the public domain in other words there is absolutely no owner ship such as copy right, trademark, or patent.

Ø Software in the public domain can be modified, distributed, or sold even with out any attribution by anyone.

Ø This is unlike the common case of software under exclusive copyright where software licenses grant limited usage rights.

3) Memories:-

Ø Memory is an internal storage area in the computer, which is used to store data and programs either temporarily or permanently.

Ø They are three types of memory

§ Cache memory

§ Primary memory

§ Secondary memory

Cache memory:-

Ø It is an intermediate form of storage between the main memory and CPU.

Ø Cache memory is very fast & very expensive the data is transferred automatically between the buffer and primary storage.

Working of the cache memory:-

Ø When a program is being executed and the CPU wants to read data or instructions

Ø First CPU checks whether the data or instructions is available in the cache memory

Ø If it is not present value there the CPU reads the data or instructions from the main memory.

Primary Memory:-

Ø So while a program is being executed it requires data so this data while is required

Ø if the data stored in R.A.M is “Volta in” that is when their power failure the data is R.A.M lost when ever new data stored in R.A.M

Ø They previous data is a raised is used to store data and programs temporary.

R.O.M:- (Read Only Memory):-

Ø Some programs are always require to run machine it is “Non volta tin” storage that is device in which data is not araised When there is power failure or it switched off

Prom:- (Programmable Read Only Memory):-

Ø In prom once the data is programmed by the user they cannot altered and modified.

Eprom:- (Eraisable programming read only memory)

Ø Eprom is that prom that can be araised and reprogram to do this It us to be removed from the processor.

EEprom:- (Electrically Eraisable program read only memory)

Ø EEprom can be reprogrammed using special electrical pluses.

Secondary Storage Devices:-

Ø Secondary storage (also known as external memory of auxiliary storage) if the data and programmers are to be stored permanently.

Ø Secondary memory is used Floppy Disks, Hard Disks, And Magnetic Taps.

Magnetic Tapes:-

Ø Magnetic tapes are mass storage devices capable of backing up and retaining large volumes of data.

Ø A magnetic tapes are used in audio tapes.

Floppy Disks:-

Ø Floppy disks are one type of data storage devices that consist of a thin magnetic storage medium encased In a square plastic shell lined with fabric that removes dust particles.

Ø The storage capacity of floppy disks is very limited as compared to cd’s 512 MB.

Optical Drivers:-

Compact Disk(C.D):-

Ø Compact disk read only memory optical disk that uses laser technology to read and write data on to disk

Ø A single CD- ROM can storage a large amount of data but once the information is stored on it.

Ø It becomes permanent and cannot be altered and modified.

DVD-ROM:-(Digital Video Disk)

Ø Digital video disk is an extremely high capacity 4.7 GB to 17 GB.

Ø Dvd are widely used to storage large databases, movies, music, complex software, E.T.C.

USB Flash Drives:-

Ø Data stored on flash drives is impervious to damages due to starches and dust.

Ø Flash Drives have higher data capacity than any other removable media, small and light weight devices.

Ø Data can read and write tough rubber or metal easing designed to be water proof and virtually unbreakable.

Ø Flash drives capacity 512 MB to 150 GB.

Memory Cards:-

Ø A memory card is a small device that can store digital files.

Ø They are easily portable from one place to another .

Ø A user can take a memory card insert into a computer store files such as text documents, pictures, audio Files & Video Files.

4) Windows Basics:-

Desktop:-

Ø Desktop is a term commonly used to describe a desktop computer or system unit.

Ø In reference to software, desktop refers to the desktop environment which is a graphical user interface metaphor that allows for interaction between the user and the operating system.

Ø Desktops is a windows sys internals utility that allows users to manage applications on up to four virtual desktops, all accessible using the tray icon interface.

Ø When referring to an operating system or GUI(Graphical User Interface)

Ø The desktop is a system of organization of icons on a screen.

Ø The Microsoft windows desktop was first introduced with Microsoft windows95 and has been included with every version of windows since then.

Ø Some of the most common icons on the desktop include those for my computer, recycle bin your internet browser, my documents.

Ø On the windows desktop you also have access to the windows start menu through the start button on the taskbar, as well as the windows notification area.

Start Menu:-

Ø The start menu is a user interface element used in Microsoft windows since windows 95 and in some other operating systems.

Ø It provides a central launching point for computer programs and performing other tasks.

Ø It has different names in different operating systems and windows managers, such as kickoff application launcher in KDE, dash in GNOME and unity, and start screen in windows8.

Ø Traditionally, the start menu provided a customizable nested list of programs for the launch.

Ø As well as a list of recently opened documents a way to find files and get help and access to the system settings.

Ø Later enhancements via windows desktop update included access to special folders like ”my documents” and favorites (browsers).

Ø Windows xp start menu was expanded to encompass various my documents folders (including my music and my pictures)

Ø And translated other items like my computer and my network places from the windows desktop.

Ø Until windows vista the start menu was constantly expanded across the screen as the user navigated through its cascading sub menus.

Icons:-

Ø An icon is a small graphical representation of a program or file that when clicked on, will be run or opened.

Ø Icons are used with graphical user interface (gui) operating systems, such as Microsoft windows and the apple mac OS, to help quickly identify a type of file or program associated with the icon.

UNIT-III

Introduction to Adobe photoshop:-

Ø Adobe photoshop is the industry-standard tool for digital imaging.

Ø Photoshop is also a good way to learn imaging concepts.

Ø Adobe photoshop is a raster graphics editor developed and published by adobe systems.

Ø Photoshop was created in 1988by Thomas and john knoll .

Ø Photoshop feature set can be expanded by photoshop plug-ins, programs developed and distributed independently of photoshop that can run inside it and offer new or enhanced features.

Sample Diagram of photoshop:-

diagram

Title bar:-

Ø This bar lists the name of the program and the title of the current document.

Menu bar:-

Ø This bar displays the headings for each drop down menu commands are grouped under each of these menu headings according to function.

Tools bar:-

Ø The tools panel is the long, narrow panel on the far left side of the work area.

Ø It contains selection tools, painting and editing tools, foreground- and back ground color selection boxes and viewing tools.

Workspace area:-

Ø You can work image editing in this area.

Pallets (panels):-

Ø The panels are available in right side of photoshop application window it consists colors, layers, history, navigation, info and more panels to help in editing images.

Image title bar:-

Ø Image title bar contains opened image title with color mode.

Status bar:-

Ø Status bar contains properties of tools and file sizes.

Creating a new document in photoshop:-

Ø You can create new, blank documents by using one of several options. Choose file-> new blank file to open the new dialog box

Ø Choose file->new->blank file in any work space or press ctrl+n

Ø Either way, the new dialog box opens.

diagram

dSelect the attributes for the new file.

You have several options from which to choose:

Name:-type a name for your file.

Preset:-

Ø From the drop down list, you can select from a number of different sizes.

Size:-

Ø You can select a preset size from a long drop down list this is optional because you can change the file attributes in the other text boxes and drop down menus.

Dimensions (width/height):-

Ø Values in width and height text boxes can be edited with out affecting the other.

Ø Adjacent to the values in the width and height text boxes you find drop down menus that offer many different options for units of measure.

Resolution:-

Ø The resolution is an independent value and is not linked to the dimensions.

Color mode:-

Ø Your choices are bitmap, grayscale, and RGB color.

Background contents:-

Ø You have three choices white, background color, and transparent, the selection you make results in the color of the blank image.

Image size:-

Ø This value (displayed in the lower-right corner of the dialog box) dynamically changes when you change the width, height, and resolution values.

Ø The reported value is how much file space is required to save the uncompressed file.

Ø Click ok after setting the file attributes to create the new document.

Save a file in photoshop:-

Ø Use the save command to save changes to the current file or the save as command to save changes to a different file.

Choose file>save as

Ø Specify a file name, location and file type like, psd, tif, png, jip

Ø In the save as dialog box select saving options

Ø Click save.

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