CS201 Lectures 23-45 by Orange Monkey

CS201 FINAL TERM NOTES

LECTURE 23 TO 45

What is programming?

Computer programming is a medium for us to communicate with computers. Just like we use “Urdu” or “English” to communicate with each other, programming is a way for us to deliver our instructions to the computer.

What is C programming?

C is a programming language. C is one of the oldest and finest programming language. C was developed by the Dennis Ritchie of AT & T‟S Bell labs USA in 1971.

The BCPL language was developed in 1967 by Martin Richards as a language for writing operating systems software and compilers.

What is C++?

C++ is an update version of C. It is also called C with close. It is an object and oriented language. It was developed by at AT& T‟S Bell lobs

Uses of C and C++

C and C++ language is used to program a wide variety of system. Some of the uses of the C and C ++ are as follows:

❖ Major parts of windows, Linux and operating system are written in C. ❖ C and C++ are used to write drive programs for devices like tablets, printers etc. ❖ C and C++ language is used to program embedded system where properly need to run faster in limited memory (Microwave, Camera etc.). ❖ C and C++ used to develop fames an area where latency is very important. I.e. Computer has to react quickly on user input.

Variables, Constant, and Keywords Variables: · A variable is a constant which stores ‟ value‟ · For example

In kitchen, we have containers storing Rice, Dal, Sugar, etc. Similar to that variable in C stores value of a constant.

Means that · a = 3; // a is assigned “3” · b = 4.7; // b is assigned “4.7” · c = „A‟; // c is assigned “A” · Rules for naming variables in C

First character must be an alphabet or underscore (_) No commas, blanks allowed.

No special symbol other than (_) allowed. Variables names are case sensitive.

We must create meaning variables names in our programs. This enhances read easily in our programs constant.

An entity whose value does not change is called as a constant.

A variable is an entity whose value can be changed.

Categories of software · • System Software · System software

System software is a type of computer program that is designed to run a computer's hardware and application programs

Sub categories of system software are: · • Operating system · • Device drivers · • Utilities

What is operating system?

Operating System controls the basic operations of the computer. It prepares the computer to provide an environment in which user communicates with the computer.

What is a Device Driver?

We will see that the operating system has installed special software to control these devices. This piece of software is called device driver software.

TWAIN stands for Technol

Utility software is software designed to help to analyze, configure, optimize or maintain a computer.

Application software (app for short) is computing software designed to carry out a specific task other than one relating to the operation of the computer itself, typically to be used by end-users.

What is an Editor?

First of all we need a tool for writing the code of a program. For this purpose we used Editors in which we write our code.

What are Compiler and Interpreter? Or Difference b/w Compiler and Interpreter?

InterpreterThe drawback of the interpreter is that the program executes slowly as the interpreter translates the program line by line. Another drawback is that as interpreters are reading the program line by line so they cannot get the overall picture of the program hence cannot optimize the program making it efficient.

Compiler Compilers also translate the English like language (Code written in C) into a language. The Compiler read the whole program and translates it into machine language completely. The difference between interpreter and compiler is that compiler will stop translating if it finds an error.

IDES stand for (Integrated Development Environment)

These IDEs contain editor, compilers, debugger, linker and loader. The benefit of an IDE is that we have all these things at the same place