It may not seem like it, but having the right font while you code can greatly increase readability. Be honest, how many times has O 0 looked the same while debugging to later realize you read it wrong? Sure we are lucky with strong typed languages but the horror is there are languages that won't flag your typos!

This GitHub repository compares lots of fonts for you to window shop just the right one to suit your need and preference.

Personally I have always like Source Code Pro since first seeing it, but now I'm giving a tweaked version called Office Code Pro a try.

Take a look at the repository here.

Alternatively you can preview them all here.