Regular expressions (regex) are a powerful tool for pattern matching in strings. Any pattern that you can define formulaically you can encode into a regex. This can be anything from a preset string with no variables to something with a particular format, like a phone number or street address. There are many tricks to learn about regex, so rather then enumerating them here I recommend you check out a few resources:
You can even use regex to help edit and reformat strings (with string methods like replace in javascript), although we won’t be discussing that here.
In this repo you’ll find a number of problems that can be solved with regex. Your goal for each problem is to write a regex that finds a match each string in the "matches" lists, but none of the strings in the “doesntMatch” lists.