HTML5 is the technology of future. Nowadays we use flash to watch animations and videos in the web. But it is going to change. In the future you need not download flash plugin for your browser. Now you can watch videos without flash support using HTML5 technology with h.264 video codec or the WebM format (VP8 codec) support. You need to use a web browser that supports HTML5 to watch videos online.
Web Browsers that support HTML5
Many popular web browsers are working to bring HTML5 technology into their browsers, because most of the browser crashes are due to the flash plugin and if it replaced by the HTML5 technology, it would increase the stability of the browser. These browsers are in beta stage, so download them and check the capabilities of a HTML5 browser.
1. Google Chrome with h.264 and WebM support, early release.
2. Firefox browser with WebM support, download it.
3. Opera WebM enabled version is also available.
4. Apple Safari with version 4+ can be used.
5. Internet Explorer 9, platform preview 3.
After downloading and installing any one of the above web browsers, you can check the HTML5 capabilities of your browser here.