Why do regexes use `$` and `^` as line anchors?

Next week is April Cools! A bunch of tech bloggers will be writing about a bunch of non-tech topics. If you've got a blog come join us! You don't need to drive yourself crazy with a 3000-word hell essay, just write something fun and genuine and out of character for you. But I am writing a 3000-word hell essay, so I'll keep this one short. Last week I fell into a bit of a rabbit hole: why do regula

[hamamuratakuo]

$ is by far the most "useless"　If we're willing to stick with it, we can also use it to explain why Ken chose ^ to mean "beginning of line". ^ isn't used in American English

[murasuke]

キーボードには必ずあって、最も役に立たない(使用頻度が低い)文字が選ばれた、ってとこか