Taken from the book 'Stranger in a Strange Land,' literally meaning 'to drink' but taken to mean 'understanding.' Often used by programmers and other assorted geeks.
It took me a long time to grok Perl, but now I can read it without going blind!
To drink in, to make a part of one's self
To grok life, love, and God, this is a noble goal
--Fred Cain
1. To understand something intimately and completely. (originally from Stranger in a Strange Land, by Robert A. Heinlein)
2. With programs, having sufficient understanding.
Almost all C compilers grok the void type these days.
To know something in and out and be able to exist in it's embodiment.
I grok Spock.
To learn and understand how something works, typically through experimentation.