A: 

According to Wikipedia, it was in B.

RegDwight
Except that according to Wikipedia it was in B.
Sorpigal
+6  A: 

http://en.wikipedia.org/wiki/Hello_world_program

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

Derick Bailey
+2  A: 

Let me google that for you.

It was written in B.

Sorpigal
A: 

When I first started programming (20 years ago) my mom told me about her Hello World program she wrote in college. She used punch cards.

Sam
Wow, somebody up-voted me. :-)
Sam
A: 

I believe that the first Hello World was written in C and published in the book The C Programming Language.

sutch
Of course! A B implementation came before the C implementation!
sutch