Regular Expressions existed before UNIX. But G/RE/P made regular expressions both expressive, and commonplace. POSIX carried the job forward, Perl had a role to play too.

One family of expression in grep, sed, awk, ed, ex and vi. Thats awesome.

What I find strange, is how late EMACS family editing came to a sensible mechanism to use them. Global search and replace in emacs has always felt significantly more 'clumsy' than in the ed/ex/vi family.

Maybe its me.