greps compose key chords so you can learn, or remember, how to type all those fun Unicode characters.
compose search-pattern
$ compose heart
<Multi_key> <less> <3> : "♥" U2665 # BLACK HEART SUIT
$ compose dash
<Multi_key> <minus> <minus> <period> : "–" U2013 # EN DASH
<Multi_key> <minus> <minus> <minus> : "—" U2014 # EM DASH