[jes5199]

I don't know if I agree - I've done plenty of setTimeouts in my life, but I can't remember if I've ever needed to cancel one before it fired, though. It seems slightly esoteric. (Then again, I don't sell myself as a front-end developer)

[mercer]

Agreed. I use setTimeout a lot, but generally don't need to cancel it. But the failure of the interviewee was not the part where he doesn't know how to cancel it, I think, but rather that he didn't know about setTimeout at all.