How "Hello, World!" program works?

hello world!

 


  • The #include is a preprocessor command that tells the compiler to include the contents of stdio.h (standard input and output) file in the program.
  • The stdio.h file contains functions such as scanf() and printf() to take input and display output respectively.
  • If you use the printf() function without writing #include <stdio.h>, the program will not compile.
  • The execution of a C program starts from the main() function.
  • printf() is a library function to send formatted output to the screen. In this program, printf() displays Hello, World! text on the screen.
  • The return 0; statement is the "Exit status" of the program. In simple terms, the program ends with this statement.

Courtesy: Programiz.com

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