What is the difference between tr and gsub?

Question

I was reading the Ruby documentation and got confused with the difference between gsub and tr. What is the difference between the two?

Answer 1

• tr can only replace a single character with a single fixed character (although you can put multiple matches of this sort in a single tr call) but is fast.
• gsub can match complicated patterns using regex, and replace with a complicated computation result, but is slower than tr.