"hello world"

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The Debian and Ubuntu Linux distributions provide the "hello world" program through the apt packaging system; this allows users to simply type "apt-get install hello" for the program to be installed, along with any software dependencies. While of itself useless, it serves as a sanity check and a simple example to newcomers of how to install a package. It is significantly more useful for developers, however, as it provides an example of how to create a .deb package, either traditionally or using debhelper, and the version of hello used, GNU hello, serves as an example of how to write a GNU program.^[2]

The first known instance of the usage of the words "hello" and "world" together in computer literature occurred earlier, in Kernighan's 1972 Tutorial Introduction to the Language B^[1], with the following code:

main( ) {
 extrn a, b, c;
 putchar(a); putchar(b); putchar(c); putchar('!*n');
}
a 'hell';
b 'o, w';
c 'orld';