Who are they? How does it all work? What would happen if captchas weren’t there?
In: 18
An easy example are forums where people post replies to threads, or websites that allow comments from readers.
If there is no way to verify it is a real person, then the threads and comments quickly fill up with spam ads, links to porn, etc.
Moderators can clean them up by deleting them, but it makes their job a lot harder if the spammers can write programs to litter their ads on every page quickly.
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