I think youtube.com is a common website for every internet user today. Everybody knows about the website and the youtube applicaton is common for every android user.
Youtube is a famous and very fast growing website for videos of any category. You just search what type of videos you want and there come many videos from where you can enjoy.
Youtube videos are of many types like entertainment, knowledge, science and technology, tutorials and much more.
You can also upload your videos simply crating an youtube chanel and also earn money.
For students you can use it for motivational and inspirational videos and also follow some tutorials availabe.