I'd say: Hello world. And not as a joke, as someone below dud. The C 'Hello, world!' program documented the style of a whole programming language in 5 lines o

I'd say: Hello world. And not as a joke, as someone below dud. The C 'Hello, world!' program documented the style of a whole programming language in 5 lines of code. Every computer engineer who sees it can now recognize C code. Even non -programmers understand vaguely what's going on. Just about every programming language today starts with the same example. That's how wildly succesfull it became as demo.