If you’ve been using regular expressions for a long time, they aren’t very hard. But learning them for the first time can be tedious. Unless you try your hand at regular expression crosswords.

Once you get the hang of regular expressions, you'll find them invaluable. The trick is to start small - I'll show you how.

The Internet has many regex resources, allowing you to learn and practice online – but here are a few pointers to get you started: Characters in square brackets [LIKETHIS] are 'character classes'.