Started in February 2005, YouTube is the leader in online video, and the most preferred destination to upload, watch and share original videos worldwide through web. YouTube was started by 3 former PayPal employees and became popular quickly. In November 2006, it was taken over by Google for US$ 1.65 billion. Today, it is one of the highest visited website where at any given minute more than 20 hours of videos are uploaded and millions of people watching them online. Today, YouTube is available with localized versions in 22 countries.

YouTube uses Adobe Flash Video technology to display a wide variety of user-generated video content, including movie clips, TV clips, and music videos, as well as amateur content such as video blogging and short original videos. It allows people to easily upload and share video clips on www.YouTube.com and across the Internet through websites, mobile devices, blogs, and email. YouTube accepts videos uploaded in multiple formats, including .WMV, .AVI, .MKV, .MOV, MPEG, .MP4, DivX, .FLV, and .OGG. It also supports 3GP, allowing videos to be uploaded directly from a mobile phone.

One of the key features of YouTube is embedding which enables its users to view its videos on web pages outside the site. Each YouTube video is accompanied by a piece of HTML, which can be used to embed it on a page outside the YouTube website be it a social networking page or a blog. YouTube Mobile was launched in June 2007, which allows users to watch videos on their cell phones capable of accessing YouTube videos.

YouTube's terms of service forbid uploading of the material likely to be considered as inappropriate and such videos are removed through flagging of such contents by its viewers. Today, many TV channels and studios have started their own YouTube channels where popular programmes of those channels can be watched. Also many political leaders, sports persons, celebrities and even terrorists use YouTube medium to reach out to the world.