What is '?' is meaning in url? [duplicate]

I'm writing code and when I type in the earthquake API link I noticed a '?' in the link and then I try to find information about it but no progress.

What is the meaning of '?' in url like this:

https://earthquake.usgs.gov/fdsnws/event/1/query?starttime=2014-01-01&endtime=2014-01-02

I'm seeing this in other sites like Youtube or google, for example: query?, watch?, count?, search?:

https://www.youtube.com/watch?v=dQw4w9WgXcQhttps://www.google.com/search?q=pi&sxsrf=APwXEdfoougSC4O6KeDi5afxiy0rL671Rg%3A1685072498601&source=hp&ei=cipwZKTQIpCUrwSHkqKgCQ&iflsig=AOEireoAAAAAZHA4gq4mE-4ZNz8m747alblR3ZAPLE84&ved=0ahUKEwik0cqdiJL_AhUQyosKHQeJCJQQ4dUDCAk&uact=5&oq=pi&gs_lcp=Cgdnd3Mtd2l6EAMyDAgjEIoFEBMQgAQQJzIHCCMQigUQJzINCAAQigUQsQMQgwEQQzIHCAAQigUQQzILCAAQgAQQsQMQgwEyCggAEIoFELEDEEMyBwgAEIoFEEMyCwgAEIAEELEDEIMBMhEILhCABBCxAxCDARDHARDRAzILCAAQgAQQsQMQgwE6BwgjEOoCECc6BAgjECc6BAgAEANQohRY9RVgvRloAnAAeACAAfABiAHRA5IBAzItMpgBAKABAbABCg&sclient=gws-wiz