Setting up multiple displays on your Mac

Setting up multiple displays to show the same image

If your computer is connected to more than one display or to a TV or projector, you can show the image on your main display on the other display. This is called "video mirroring."

1. Open System Preferences and click Displays.
2. Set both displays to the same resolution and color depth.
3. Click Arrangement and select Mirror Displays.

Source: http://docs.info.apple.com/article.html?path=Mac/10.4/en/mh1551.html

Setting up multiple displays as an extended desktop

If your computer is connected to more than one display or to a TV or projector, you can set them up as a continuous display for your desktop.

1. Open System Preferences and click Displays.
2. Click Arrangement and follow the onscreen instructions.

Source: http://docs.info.apple.com/article.html?path=Mac/10.4/en/mh798.html

Note: You can access most of the above options from the Displays menu icon, in the top right corner of the screen (pictured below).