In general, unless you’re a schoolteacher (and at the moment in the process of executing that job), I find it pretty rude to correct other people’s spelling. (Probably this has something to do with the fact that I’m not a good speller myself.  Case in point: I had to look up persuer for this very article.)  Not everyone can spell. Not everyone has English as a first language. So as long as their idea comes across, I don’t care how people do it.

However!

Sometimes it matters.  The following are all examples I’ve seen recently, and… seriously… it’s worth a mention.

“I’m waiting with baited/bated breath.”
Baited means you’ve been eating worms.
Bated means to abate, to lessen, to hold back, i.e. “I can’t breathe.”

Example #2:

“I am tired of looser/loser old men hitting on me.”
Looser means un-tight.  In other words, they might have bowel problems.
Loser means un-winner.

Example #3:

“Please bare/bear with me.”
Bare means naked.  So it turns the phrase into a proposition.
Bear means “hang tight”.  More or less.

Learn these. Trust me.  Unless of course you’re a worm-eating, naked-lovin’ person with bowel afflicted persuers.  In which case, as you were.