you can “track” a word. This will subscribe you to any post which contains said word. So, for example a student could be interested in how a particular word is used. They can track the word, and see the varied phrases in which people use it. Or, you can track an event, a proper name (I track Derrida for example), a movie title, a store name see how many people a day tweet that they are at or on their way to a Starbucks. (To do this send the message “track Starbucks” to Twitter, rather than posting the update “track Starbucks” you will now receive all messages with the word “Starbucks.”)