Twitter was the first micro blogging service, and it continues to be dominant. Twitter users have their own vocabulary. When blogging, we speak of "blog posts." Twitters short posts are called "tweets." In blogging we say we will "subscribe" to someone's blog. In Twitter we say we are "following" the person.
Since the messages are short, people often read and post to micro blogs using their phones or other mobile devices. (You can also receive tweets as text messages on your phone).
Twitter began as a text service, but one can incorporate links to audio and video files in a tweet.
URL abbreviation services like TinyURL help us keep our tweets short (under 140 characters). Common abbreviations like "LOL" for "laughing out loud" or "u" for "you" also save characters/.
If you think Twitter sounds frivolous, check out this site and book about the use of Twitter in business by tech journalist Julio Ojeda-Zapata.
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How might we use Twitter in our class?