INTRODUCTION TO COMPUTER INTRODUCTION TO COMPUTER PROGRAMMINGPROGRAMMING

itc-314itc-314

LECTURE 01

Course GradingCourse GradingTotal Marks: 100 (Theory)

60 Marks = Final paper 20 Marks = Midterm Tests 10 Marks = Assignments 05 Marks = Presentations 05 Marks = Class Performance

Practical: Total Marks: 100 80 Marks: Final Practical 10 Marks: Lab Tasks10 Marks: Lab Performance

Overview:-Overview:-The term” Computer Programming” refers to create a

set of instructions that enable computer to do something.

Computer Programming is very important course in the field of Information Technology as the topics covered in it will be encountered by you again and again in the future courses.

The study of computer science teaches us how to use computers, how to organize the data and also how to create programs that can be used by computer to solve problems.

GoalsGoalsThe aim of this course is to understand what

is computer programming, why we learn programming, what are the programming languages, what are categories and generations of languages, what steps are needed to create a programs by using different computer languages etc.

In this course we will also discuss about various programming languages that can be used to create programs.

In this course we will mainly emphasize on C programming language.

Introduction to ComputersIntroduction to Computers

Computer

A computer is an electronic device which converts raw data by processing into meaningful information.

The word “computer” comes from the word “Compute” which means to calculate. Hence, a computer is normally considered to be a calculating device, which that perform arithmetic operation and logical operations at enormous speed.

DATA DATA Data are simply values or set of values.The English word Data is a plural of word Datum, which

means fact. Therefore, we can say that Data means facts.

Data is a group of characters (digits, alphabets, or other characters) which represents a specified value or condition.

ORData consists of raw facts, which the computer can

manipulate and process into information that is useful to people.

Some examples of data items:3, 5, 99, 50A1, F16, AB-10, Islamabad, Karachi, Asad

InformationInformation

The organization of data in a meaningful form is called Information.

ORMeaningful or processed data is called

Information.

Example: 2 + 3 = 5Data Information

Basic Components of Basic Components of ComputerComputer

A computer system can perform variety of tasks according to specific instructions.

These tasks are perform by computer by using its components.

A digital computer system is totally based on its components that are attached or installed in it.

There are two main components of a computer system.1) Hardware2) Software

HardwareHardware The physical components of computer system is

called Hardware. Hardware is also known as Tangible part of the computer.

OR A computer’s hardware consists of electronic

devices. The parts you can see and touch.

The term ‘device’ refers to any piece of hardware used by computer, such as keyboard, monitor, modem etc.

A computer’s hardware devices are categorized as follows:

i. CPU or Processorii. Secondary Storage or Backing Storage iii. Input Devicesiv.Output Devices

CPU or Processor CPU or Processor

The Processor is also called CPU. CPU stands for Central Processing Unit.

CPU is also called brain or heart of computer. It manages all the devices and performs the actual processing

of data, means all processing, manipulating, mathematical, logical operations and temporary storage are done by CPU.

It has the following three parts:◦ Arithmetic Logic Unit (ALU)◦ Control Unit (CU)◦ Memory Unit

ALU: ALU performs all the arithmetic and logic operations. CU: Control Unit is responsible for coordinating all the

operations of the entire computer system. It also arranges to get programs instructions from memory, interprets them and has the desired action performed.

MemoryMemory Memory is a storage area where all the programs and required data are

stored. Two Types.

◦ Main Memory / Primary Memory◦ Secondary Memory / Backing Storage

Main Memory: used to hold programs and data, that the processor is actively working with.

Main Memory is not used for long-term storage. Main Memory consists of RAM and ROM.

RAM: Ram is used for storing temporary data during the working of computer. RAM stands for Random Access Memory. It is a volatile memory means it hold data only while the computer is on. Once the computer is off, all the data in RAM will be erased.

ROM: Rom stores permanent data or instructions that are provided by manufacture at the time of purchase. This contains mostly instructions for starting the computer. ROM stands for Read Only Memory means it cannot be erased and we cannot store or write over it.

Secondary Memory Secondary Memory

used to hold programs and data for long term use. Examples of secondary memory are cd-rom, floppy disks, USB

flash drives etc. considered as non-volatile storage. Comparison between main memory and

secondary memory

I/o devices: I/o devices: The Input / output devices are necessary for human beings to

interacts with computers. Input Devices: The input devices are used to feed data and

programs into computer. Input devices accept data and instructions from the user or from

another computer system. Data and instructions must enter the computer system before any

computation can be performed on the data. This task is performed by the input unit.

The following functions are performed by an input unit.i. It accepts data from outside world through an input device.ii. Convert these data into computer usable form.iii. Supplies the converted data to computer for processing. Some examples of input devices are Keyboard, Mouse, Trackball,

Light Pen, voice synthesizer etc.

I/o devices Cont….I/o devices Cont….

Output Devices: Output devices return processed data back to the user or to another computer system.

The job of an output unit is just reverse of an input unit. Following functions are performed by an output unit.i. It accepts the result produced by computer (CPU).ii. It converts these coded result to human acceptable(readable) form.iii. It supplies the converted results to the user through an output

device. Some examples of output devices are Monitor and Printer.

HARDWARE HARDWARE COMPONENTSCOMPONENTS

INPUT OUTPUT

MEMORY

CU

ALU

SoftwareSoftware

Software (also called programs) consists of organized set of instructions for controlling the computer. Software is also called intangible part of a computer.

OR Software is a set of electronic instructions that tells the

computer how to do certain tasks. A set of instructions is often called a program.

The two most common types of programs or software are system software and application software.

System SoftwareSystem Software

System software are consists of programs that controls the overall operations of system.

System software are used to help the computer to perform specific functions

System software are needed to keep all the hardware and software systems running together smoothly.

One major type of system software is the operating system (OS).

The OS tells the computer how to interact with the user and its own devices.

Examples: Operating Systems like Linux, Windows, Unix, Solaris, MacOS.

Application SoftwareApplication Software

Software that are create to perform a specific function is called Application software.

Application Software are used by people to get their work done.

Application software tells the computer how to accomplish tasks the user requires, such as creating a document or editing a graphic image.

Some important kinds of application software are: Word Processor, Game programs, Spreadsheets programs, Database

programs etc.

Basic operations of Basic operations of computercomputer:: All computer systems perform the following five basic

operations, for converting raw data into the information, which are:

Inputting: The process of entering data and instructions into the computer system.

Storing: Saving data and instructions to make them readily available for initial or additional processing as when required.

Processing: Performing arithmetic operations or logical operations on data to convert them into a useful information.

Outputting: The process of producing useful information or result for the user, such as visual display or printed report.

Controlling: Directing the manner and sequence in which all the above operations are performed.