Comment by warbiscuit

One bit of trivia I really love is why "DEL" is at 127 -- weirdly way away from all the control codes.

It's because 0x7F is all ASCII bits set to "1". Back in the early punch card (and telegraph?) days, if there was a typo, you couldn't "unpunch" a hole to make it a 0 again, but you could punch out all the rest of them, indicating "ignore this char, I've deleted it" -- 0b1111111.

source: http://www.trafficways.org/ascii/ascii.pdf which is a really neat read if you like that sort of thing :)