Language Details: AWK

AWK uses a data-driven scripting language consisting of a set of actions to be taken against textual data (either in files or data streams) for the purpose of producing formatted reports.

AWK article on Wikipedia
Code Jam 2010 Contestants using AWK
Qualification Round
Used in 8 solutions by 4 contestants:
Round 1B
Used in 2 solutions by 1 contestants:

Submission Origin

China (1 contestant)
Costa Rica (1 contestant)
Hungary (1 contestant)
India (1 contestant)