The laptop trackpad has come a long way since Apple Inc. pioneered it 14 years ago on the PowerBook 500 series as a replacement for the trackball found on earlier models.

While almost anyone who has ever used a laptop knows the basics of using a trackpad as a pointing device (simply drag your finger over its surface to move the cursor on-screen), not everyone knows about all the features that Apple has added to its trackpads over the years.

Depending on the Mac notebook model, there are up to 10 specialized trackpad functions you can use to make navigating the screen, Mac OS X and various applications faster and easier.

The trackpad options discussed in this article are not enabled by default; you can enable them all in System Preferences using the Trackpad tab of the Keyboard & Mouse pane. The exact look of this pane will vary depending on the Mac model and on the version of Mac OS X installed, but most will look something like the figure shown below. Some options require hardware support and thus are available only on specific models.

In this article, I'll look at each of the trackpad functions, beginning with the most basic and widely supported and moving on to the latest and greatest options available only on new MacBook Air and MacBook Pro models.

Basic one-finger features

The most basic set of options for Mac trackpads are performed with single-finger motions. These options have been around since long before Mac OS X; they're supported on every Mac notebook since the original iBook, as well as a handful of earlier PowerBooks.

Although widely supported, many novice users (and some experienced Mac users) aren't aware of some of these features or their usefulness. Single-finger options include tap to click, tap and drag, and drag lock. They're pretty basic, but they save time and make using the trackpad more intuitive.

Tap to click: Probably the most underrated of all trackpad options is tap to click (called simply "Clicking" in the screenshot to the right). When it's enabled, a single tap on the trackpad acts as a mouse click.

This allows you to easily make selections without changing your hand position. Simply move the cursor over the item you want to select or button that you want to click, and tap your finger.

Dragging: With dragging enabled, you can tap on an item (such as an icon, a window's title bar, or text) to select it and move your finger without lifting it off the trackpad. The selected item drags around the screen the same as if you were holding a mouse button down. Lift your finger off the trackpad, and the item is released as if you had taken your finger off the mouse button.

Drag lock: It isn't uncommon to run up against the edge of the trackpad when you're dragging an item across the screen, which can lead you to drop the item someplace unintended. That's where drag lock comes in.

The effective use is the same as dragging, except that the selected item isn't released when you lift your finger. If you reach the edge of the trackpad, just reposition your finger and keep dragging. A second tap of the trackpad (or a click of the trackpad button) releases the item.