While the Twitter Rules article contains our comprehensive list of account behaviors that could land you in hot water, this page is a basic introduction to Twitter's rules and best practices related to some of the most common questions on Twitter best behavior.
Automated pro-active following and automated un-following are not allowed. If an account seems interesting, feel free to follow it! When you follow someone, they will often take the time to check our your profile and recent Tweets. If some accounts are aggressively or indiscriminately following hundreds of accounts just to get attention, it can really bother other users and make Twitter a less-nice place to hang out. Our Following Limits and Best Practices article has all the information you need for good following on Twitter!
You can direct a Tweet at a specific Twitter user using @replies and mentions. The @reply feature is intended to make communication between users easier, so please don't abuse it by posting duplicated, unsolicited @replies to lots of users. This is considered spam behavior!
Participating in Twitter trends is a great way to join a worldwide public conversation. Our Trends help page has information on how to join in. Please don't post unrelated Tweets to trends in order to get attention—your account may be suspended!
Search (and contests)
Twitter search is a powerful way to find out what folks are talking about, right now. We may filter accounts from search if they're degrading the search experience for other users (by posting lots of duplicate links, for example). Our Search Troubleshooting article has all the best practices for remaining in search. People wanting to run a contest on Twitter should check our Contest Guidelines page for some rules and helpful tips.
Thinking about adding some account automation? External developers have created some amazing tools and services for the Twitter community. Take a look at our Automation Rules and Best Practices for a discussion of the best ways to automate your account without spamming or bothering other users!
Check out our complete list of articles outlining our policies, guidelines and best practices.