basic defination & its uses.

#include:- It is a preprocessor complier or directive.
iostream:- It use for input & output stream.
    .h:-        It is header file. A file containing CPP tokens to set the particular model resolution and configuration named with a ".h" suffix {example= include.h}.
conio:-      It used for console input & output.
complier:-   A program that translates a high-level language, such as BASIC, into machine language. A compiler is a computer program (or set of programs) that transforms source code written in a computer language(thesource language) into another computer language (the target language, often having a binary form known as object code). The most common reason for wanting to transform source code is to create an executable program.
main():- The main program start, with keyword main(), each program must have a main() function.
curly Braces{}:- All the coding is include in the body of the main program in the curly braces{} & } end the coding for the program.
getch():- getch is used for get the result or output.