Awk tool

a command-line text manipulation tool
, as well as a scripting language.

differences with grep
awk is a interpreted programming language,
where as grep is a compiled c-code program (which is additionally optimized towards finding patterns in files).

As a rough guide:
- searching for lines matching a substring or regexp? Use grep.
- selecting certain columns from a simply-delimited file? Use cut.
- performing pattern-based substitutions or … other stuff sed can reasonably do? Use sed.
- need some combination of the above 3, or printf formatting, or general purpose loops and branches? Use awk.