Unicode is quite interesting, not just for fun emoticons 👽 and math ∑. Because, when you go deep, it is about ALL grapheme and logographs and symbols of ALL human's writing systems, past and present. For each, there's long history, and how it all synthesize into a writing system, often with deep connection to culture.
Missing font? see: Fonts for Unicode 6 Emoticons
For programers: Unicode for Programers: Essays Index