What is reputation and how do I earn it?

Reputation is the site's record of whether other members found your posts useful. It goes up when someone upvotes your question or answer, and when the person who asked accepts your answer. It goes down when a post is downvoted.

Reputation is not a score to chase. It unlocks the moderation work: as it grows you can vote, edit other people's tags and posts, and eventually review edits. New accounts can ask, answer and comment from the first day.

The fastest way to earn it is to answer a question in a state or a topic you actually live with, and to say where your figure comes from and when you last checked it. Answers that name a date and an official body get accepted more often than answers that do not.