Used both as noun and verb, a tweet is a posting on Twitter as well as the act of posting to Twitter. For example, "I liked her tweet" and "I like to tweet." See
Twitter.
Tweets and Fleets
Tweets remain in the recipient's device while "fleets" automatically disappear after 24 hours. According to Twitter, fleets are used to share in-the-moment thoughts with followers. See
retweet,
tweetstorm and
tweeter.