YouTube is the most well-known video service on the Internet. YouTube lets anyone share videos online, either from their hard drive or recorded using their computer's Webcam. It uses Adobe Flash and a simple video player that starts playing videos the moment you launch the page housing the video.
No doubt about it, YouTube has paved the way for a variety of other services and evolved its own services with new features such as user profiles, video rankings, and a system that lets anyone reply to a video either with text or another video. You can also easily embed videos on Web pages and share them via Facebook or Twitter with the click of a button. It has also introduced some controversial features such as video viewing history, and displaying who's watching a video at the same time you are.
In the past year, YouTube rolled out high-definition video, a completely redesigned homepage, and a tool that tracks what you're watching and shares it with others in real-time. The site is also rumored to have a live video service in the works. The service has dealt with its fair share of copyright infringement issues in the past, but that doesn't mean you can't still find great (and sometimes questionable) content to keep you entertained. It's a great site to have bookmarked.