In the last few years the functionality cost of running Linux operating system shrunk. Good hardware support is one of the last things Linux is lacking when compared to other operating systems. That isn't really Linux community's fault. The hardware manufacturers are to blame for not supporting their own hardware on operating systems other than the proprietary ones. The Linux community developers are actually doing miracles with hardware support and I thank them on doing such a great work. Web cam support was once blind spot on Linux supported hardware list.
How to install webcam (camera) driver on Ubuntu ? (No device found) - Ask Ubuntu
Grr this took hours to figure out. See also: How to run webcam software only when I am not home. There is a lot missing from the instructions, like setting the frame rate and other settings in the motion. There are many good tutorials on setting up motion as a web cam.
More info Needs Updating This article needs updating to include the latest versions of Ubuntu. Trying to setup and use your existing webcam.