Twitter is an online, microblogging site. Users post short messages that can often include a link, share messages from other users and communicate directly with other users. Users sign up for a user account that can be used to follow other users that they are interested in. Here is the link to the twitter Help Centre page on How to create an account.
Username or Handle: The name that other Twitter users use to communicate with you. Example: TweetHumanDev
Tweet: A post on twitter (noun) OR to post on twitter (verb). Example: Did you see my tweet? I tweeted about Assisted Reproductive Technologies.
@ Mention: The @ symbol before a user name will bring that message to the attention of that user. Example: @fuzzy_smile - hmmm interesting!
Hashtag: # followed by a relevant keyword or phrase (no spaces). Hash tags are a way to categorize tweets - clicking on a hashtagged word will bring up all other tweets marked with this keyword. If enough people use the same hash tag at once, the term will appear in Twitter's trending topics. Example: #bio380
Trending Topics: The most mentioned terms on twitter at a given moment. Trending topics aggregate many tweets at once and change constantly. Trending topics may include hashtags. Example: Romneycare
Follower: Someone that is subscribed to your tweets
Following: Subscribing to another users tweets
Character Limit: Each tweet cannot exceed 140 characters (including links)
Link Shortner: Links will be shortened to conserve characters. Some sites that do this are http://bit.ly or http//tiny.cc