Scroll Reverser is a free Mac app that lets you choose a different scrolling direction for your Mac's trackpad and a physical mouse.

Computer mice often have scroll wheels or multiple buttons. The middle-click function works as a shortcut in many programs; here are some tips for using it.

If your mouse wheel feels jerky or scrolls the wrong way, here's how to get back to smooth scrolling.

You can do that with your mouse, too. Click your desktop background, hold CTRL on the keyboard and scroll your mouse wheel up or down to increase or decrease the size of your icons.