I am easily amused

[redbird]

I just emailed the Arlington Library to ask about their privacy policy. Their anti-spam feature, to prove I'm human, was an arithmetic question. Any robot worth its salt can answer "9+14=?" but apparently the bots aren't programmed to recognize the question (displayed in the same way as "Name") or to call an appropriate routine and enter the answer.

Comments

[flippac]

It's mostly about how much processing power the bots would need. Rendering the image is a lot cheaper than OCRing it - it's what the military folks call a force multiplier.

And if it's just text, introducing it via javascript means the bots risk being asked to do an unbounded amount of work or even being cracked (you can run meltdown and spectre attacks from javascript). Again, not good for the bots.