I want to control robot from internet. Do i need Rosbridge or is there any other way??

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In general, adding 'from [the] internet' to your question doesn't really add much to the already asked question.

If, by 'from [the] internet', you mean 'on a computer connected to the internet', networking is already baked into ROS, so rosbridge is not necessary. You need to learn about the ROS_MASTER_URI and possibly the ROS_IP environment variables.

If, on the other hand, you mean 'from within a web browser', then yes, rosbridge can serve as a tool to help you do that. You can look at the list of experimental ROS client libraries; specifically, you'd likely be interested in rosnodejs. Even more specifically, you should look into robot web tools, and even more specifically than that, at the Widgets section on the Tools page.