The ubiquitous mouse has become one of the most important and effective tools for interacting with the computer.
There are a couple different kinds of computer mice but they all pretty much do the same thing. They move the pointer around the screen so you can select different things.
Clicking and Double Click is not only hard to explain but at first it's pretty hard to do too. Here's is a great website that can help you practice this important skill: MouseProgram.com/
There is also an activity at that website to help you practice Clicking and Dragging.
If you have an older computer mouse it probably works on a track ball which is located under the mouse. Occasionally this track ball will get dirty and your mouse pointer will skip around the screen randomly. When this happens you can easily fix it by opening the bottom disc that holds the track ball in and then removing any foreign objects that might be causing the mouse to behave erratically.
If you have a newer computer mouse you probably have an optical mouse. These mice are much more reliable since they have no moving parts and will work on just about any surface. If you’d like to learn more about how they work you can check out this website: http://computer.howstuffworks.com/question631.htm
The advantage to this new kind of mouse is that it has no moving parts. And the red LED light isn’t any more dangerous than a flashlight (it’s not a laser beam).