A "Hello, World!"program is a computer program that outputs or displays the message "Hello, World!". Because it is very simple in most programming languages, it is often used to illustrate the basic syntax of a programming language and is often the first program people write.
Hello World. A "Hello world" program is a computer program that outputs "Hello World" (or some variant) on a display device. The first known version of this program comes from Brian Kernighan’s paper A Tutorial Introduction to the Language B from 1972 (chapter 7).