@ireneista @cmconseils okay I went to double check because they do have names but I know that they're a weird unofficial thing meant to make discussing the game in the abstract easier.
And I found this: https://www.huffingtonpost.co.uk/entry/i-just-learned-the-names-of-tetris-blocks-and-theyre-perfect_uk_66b4a6e8e4b042ee2cd02cd3
Apparently, this joke fooled Jeopardy.