But we can't always "avoid" using it... so sometimes we have nothing but to use the Touch-pad. Since it's touch sensitive... sometimes when you type... if you accidentally touch the pad then the mouse pointer would dance bit here and there, especially if you're not a touch typist, then most of the time you won't be looking at your screen while typing so you'd just type few words to realize that they simply didn't get insert into the text editor because your mouse pointer was elsewhere >:( , bugger can be pretty annoying, sometimes :).
In those cases, wouldn't it be nice if you could automatically or easily disable your Touch pad whenever you plug-in your Mouse?. That's exactly what the TouchPad indicator does. It's a simple applet that runs from the background and lets you enable/disable your GNU/Linux Laptop's touch-pad with ease (either by a shortcut or automatic disabling when a "mouse" is detected).
If you use Ubuntu 11.04 Natty Narwhal or 10.10 then you can install Touchpad Indicator by entering the below command in your Terminal.
sudo add-apt-repository ppa:atareao/atareao
sudo apt-get update
sudo apt-get install touchpad-indicator