They started as same word, but their meanings have drifted apart over time.
Often used, often confused. Here's some guidance and insight.
Why both words are equally good for you.
Why does it sound strange to say 'funner' or 'funnest?'
We'll tell you all the perpendiculars
How 'literally' can mean "figuratively"
'Between you and __'? Simple guidance for a tricky pronoun.