Please could anyone give me html code for online video streaming?
Depends on the video. If you're embedding from YouTube or Vimeo or other popular video sites, they'll provide the code that you need in order to put the video into your webpage.
If it's a video that you have on, say, your web server, then you'll need different code altogether.
Yes, hosting services like YouTube and Vimeo are the easiest option, as you then just embed their code in your pages. Or you can use something like FlowPlayer to host the video yourself.
It's not clear, though, if you are asking about solutions to play videos on your site, or asking about the kind of video streaming offered by bigger sites like Netflix.
i mean how to give my visitors option to play videos hosted on my server
<video src=myvideofile.webm controls></video>
^ except with alternative children inside.
You need to upload video player to play video from from your hosting. You can do this
You could go with a cloud based video sharing service that encodes the video and allows you to stream it on any platform. The platform you select will provide you with the script <snip>