Here’s what you need to look out for.
Clear and easy-to-read characters to reduce eye strain when spending hours looking at hundreds of lines of code.
Makes a clear distinction between commonly-confused characters such as the letter “O” and the number “0” or the lowercase “L” and the number “1”.
Ligatures or extra whitespace for commonly-used symbols in popular programming languages – not for everyone, but others love it.
Fonts with multiple variations on how certain characters are handled are great, so you can pick and choose exactly the version you prefer.
Many programmers prefer monospace/fixed-width fonts to help readability and make code easier to scan for errors, so most of them fall under that category. Some of them contain standard, non-monospaced versions bundled in if you prefer it that way.