Have you ever seen a link with a bunch of extra stuff on it? Facebook URLS with “fbclid=<big string of letters” or links with a bunch of “utm_medium=<whatever>” or those horrendously long product links you get from Amazon?
They’re used for tracking behavior, and handy for people getting marketing and attribution data. If you don’t mind them, that’s cool. They annoy me a little because I like clean, readable URLs.
There’s a browser extension to get rid of them, called ClearURLs: