Regex Cheat Sheet

Greedy. A quantifier like .* consumes as much as it can and then gives characters back until the rest of the pattern matches. Adding ? makes it lazy, so .*? consumes as little as possible. Lazy matching is usually what you want when extracting content between delimiters.

Whenever you need grouping for alternation or a quantifier but do not need the captured text. Writing (?:…) instead of (…) keeps your capture group numbers stable and meaningful, which matters as soon as a pattern has more than one group.