The word "grok" originated from science fiction author Robert A. Heinlein in his 1961 novel, "Stranger in a Strange Land". In the novel, "grok" is presented as a Martian word, not a literal one, but a way of expressing deep, empathetic understanding.  My attraction wear will support you in this high-profile fit green undervisor cap; a classic with an added pop of color.  Only from My Attraction Wear. • 100% cotton twill • Structured • Five panel • High profile • Green undervisor • Sewn eyelets • Snapback closure