I remember this kanji because when we learned it, one of my classmates made up a sweet mnemonic to remember the word 条件（じょうけん）. He knew that it had the 人弁 (にんべん, person radical), so he gave both of the characters names – Joe and Ken.

条件 is a useful word. It means conditions, as in the conditions on a contract or the conditions/prerequisites for an application.

件 by itself is also pretty useful. My teacher in Tokyo used to make us use it in the subject lines for emails, e.g. 期末テストの件 (a subject I used back then), 小学校訪問の件 (a subject line I actually use now), or 田舎ビール種類不足の件 (a topic that I would like to raise now). Basically it is the “RE:” that you see (or used to see…has this died out?) in the subject lines for emails meaning “regarding such and such.” It’s an easy way to make your Japanese emailing more professional.