Using “find whole words only” comes in hand when editing your writing for the word “OK.” People commonly spell/punctuate/capitalize this inconsistently (OK, okay, Ok, Ohkay, O.K.), but the series of letters can be part of many other words.
So if you’re doing a search for ok, it’s appropriate to check the back for “whole words only,” to make sure you don’t pull up words like spoke or stroke or book, look, or took.
How many ways have you seen to spell OK? What’s your default?
Fun fact: CMOS prefers OK but defers to author preference as long as there’s consistency. APA Style does not state a preference, as OK is simply seen as nonacademic and inappropriate.
Personally, I prefer okay, but oh well.