What are the key features of C language or what are the characteristics of C language?

• Embedded C is the extension of C programming language.
• Embedded C is used to develop micro controller based applications.
• Embedded C includes features not available in normal C like fixed-point arithmetic, named address spaces, and basic I/O hardware addressing.
• Cell phones, MP3 players are some example for embedded systems in which embedded C is used to program and control these devices.

• C language is belonging to middle level language. C language behaves as a bridge between machine level (low level) languages and high level languages.
• C language is more user friendly than machine level languages. And, C language does not support all the concepts that high level languages offer. So, C programming language is called as middle level language. 

High-level languages –

• These level languages provide almost everything that the programmer might need to do as already build into the language.
• Example: Java, Python

Middle-level languages –

• These languages don’t provide all the built-in functions found in high level languages, but provide all building blocks that we need to produce the result we want.
• Example: C, C++

Low-level languages –

• These languages provide nothing other than access to the machine’s basic instruction set.
• Example: Assembly language.

• Compiler is a program that converts human readable code into machine readable code. This process is called compilation.

• Assembler is a program that converts assembly level language (low level language) into machine level language.
• Compiler compiles entire C source code into machine code. Whereas, interpreters converts source code into intermediate code and then this intermediate code is executed line by line.

• printf() is an inbuilt library function in C which is available in C library by default. This function is declared and related macros are defined in “stdio.h” header file.
• printf() function is used to print the “character, string, float, integer, octal and hexadecimal values” onto the output screen.

• scanf() function is an inbuilt library function in C which is available in C library by default. This function is declared and related macros are defined in “stdio.h” header file.
• scanf() function is used to read character, string, numeric data from keyboard.

• The protocol is nothing but a set of rules to be followed by a programmer.

Always, execution of a C program starts from main() function.