Is javascript what I need?

[Led]

I would like to make an application that would run on a webpage.

The application needs to be able to accept user inputs (like the radius of a circle) and then be able to draw an object (like a circle) based on the input.

I might also want to use a mouse and move the object (center of the circle) around on the screen.

Is Javascript (or Java, or something else) what I need to use?

Thanks 

[SleepKiller]

Given how such amazing classics like Cookie Clicker are written in Javascript I would imagine it would be more than passable for your use case. Though I'm no web developer so some of the more Web-savy folk around here may have a more valid opinion.