Site #4: TED

1. Core purpose is explained in it's opening statement: 

Riveting talks by remarkable people, free to the world online

This site shows what the statement means, as soon as the user clicks on to the index page, it is confronted with about 20 videos of talks that have been done at TED. TED makes them all available to users, free of charge, online. It's purpose is to be accessible and knowledgeable while being interesting. 

2. The site accomplishes this by being easy to use, well defined and fast. There are thousands of videos on the side and using the search bar definitely helps, it is easy to use and knows what its doing. 

3. Unique features include the conversations tab, where users ask questions for anyone to answer, sharing world views etc. Has all the usual bells and whistles too, blog, events, conferences, tickets etc, all clearly laid out at the top of the page every time. No chance of getting lost. Or bored.

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