Gawk provides the additional features found in the current version of Brian Kernighan's awk and a number of GNU-specific extensions. … As for speed, using gawk as "plain" awk should make no difference – often, when gawk is installed, awk will just be a symlink to gawk which means they'll be exactly the same program.

Is awk still relevant?

AWK is a text-processing language with a history spanning more than 40 years. It has a POSIX standard, several conforming implementations, and is still surprisingly relevant in 2020 — both for simple text processing tasks and for wrangling "big data". ... The language was created at Bell Labs in 1977.

Is awk efficient?

Awk is a compiled language. Your Awk script is compiled once and applied to every line of your file at C-like speeds. ... Awk is much faster. I say this with no disrespect for Python, it's just you should know the tradeoffs of the tools you use.