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Twitter is a Web 2.0 tool that allows users to create short 140 character blog entries. Within these microblogs, users can post photographs, links and group their blogs into categories using hashtags. Twitter users can follow friends and hashtags to recieve the relavent blogs on their newsfeed, and other twitter users can follow them.

Twitter would be useful in a classroom setting as a way for students (who are over the age of thirteen) to share material, resources and opinions with one another in a fast and easy manner. Hashtags would ensure that all posts from students on a similar topic could be found in one place, and the ability to reply to posts others make could create opportunites for conversation and debate on class materials. 

Learners who have difficulty focussing and reading extensive material would benefit from twitter because the maximum length the post can be is 140 characters. These students could read the short individual posts to learn and then contribute without having to worry about reading and writing difficulties.