Youtube.com is the leader if you talk about online videos. I have been using Youtube from years.
On youtube, you can watch anything, you just search it and u will find it on youtube.
Whether it’s movie trailer, sports, comedy, any serial u missed or any tutorial you want to see( it’s fulfilling wishes like a genie) . Now a days, there u can also see a great no of channels who r impressing everyone in comedy like tvf, aib etc.
Also, you can earn money by creating your own channel and uploading videos on youtube.An all in one site for everyone.Highly recommended.