Twitter is a social networking website that allows users to post tiny messages called "tweets." Tweets can be made private, but most are public and available for anyone to search. You can search tweets on Twitter using a specific keyword or phrase, which will pull up a list of all public tweets that may be relevant to your search. You can then follow the profile that posted the tweet you're searching, or can mention the tweet in a tweet of your own.
Go to Twitter (twitter.com) using your Internet browser.
Log into your Twitter account if you have one, or create an account by clicking "Register." Enter your personal information, then confirm the account by clicking the confirmation link in the confirmation email from Twitter. It is also possible to search tweets without registering.
Click the "Search" field and type your search term. If you want to find all tweets about cats, for example, type "cats," then press "Enter." A list of public tweets containing that term will appear.