Wordle is pretty damn smart in many subtle ways
I actually think the OP and the comments are too focused on the programmer-related aspects of this. I'll add a few things.<p>1. It's not trivial but it's not that hard if you have a decent vocabulary and some intuitive sense for word frequencies (and word pair frequencies) for different locations in a word. The answer list does not seem to include really hard words as naively picking all the words in the MW dictionary would be. It's a fun 10-15 minute puzzle.<p>2. Five letter seems like something of a sweet spot.<p>3. The answer word list does not appear to have a lot of plurals or common vowel endings for past tense, etc. Or obscure words.<p>4. It lends itself to what I'll casual cheating, i.e. there are easy ways to get some hints without giving the answers away while focusing on a strategy.<p>5. Basically, it's got good gameplay for a casual game. It would be easy to build something along similar lines that didn't have as fun gameplay for a casual gamer.