Getting started with C Language (1)

Character set in C language:

Character set denotes the alphabets, digit or special symbol used to represent information.

Alphabets	A, B, C, ----, Z a, b, c ----, z
Digits	0, 1, 2, 3, 4, 5, 6, 7, 8, 9
Special Symbols	~ ` ! @ # $ % ^ & * ( ) _ - + = | \ { } [ ] ; : ” ’ < > , . ? /

• Raw code: It is a code which can run without OS. example: .hex code(as it deployed in 8051 and it does not contain OS)
• Executable code: it is a code which cannot run without OS, OS is needed for this type of code. example: C code.

Compilers:

Compilers convert human readable code into binary code or machine understandable code.

Types of compilers:

1. Native compiler
2. Cross compiler

Native compiler:

The compiler working in one environment and generating machine understandable code for same environment is called as native compiler.

Example: Turbo C, Dev C++, etc.

Cross compiler:

The compiler working in one environment and generating machine understandable code for other/different environment is called as native compiler.

Example: Keil IDE, MP Lab, etc. (like we write c code in windows platform and convert it into .hex file and deploy it on microcontroller)

Difference between Native Compiler and Cross Compilers: 

Native Compilers	Cross Compilers
Generates code for same environment	Generates code for same environment
They are used to build programs for same environment	They are used to build programs for different environment
System dependent	System independent
It can generate .exe file	It can generate raw code like. hex file
Example: TurboC or GCC Compiler	Example: Keil IDE