With the advent of set-top boxes, Internet streaming and HD-enabled computers, television and online viewing have collided in a major way. Many computers now include several video ports to accommodate connecting to a high-definition TV. Whether you have a Mac laptop or desktop, connecting the computer to your TV is a basic task, but you will need a few accessories to complete the project. Macs of recent vintage have DisplayPorts for video-out connections. To connect your Mac to an HDMI TV, you will need an adapter. MacBooks and iMacs use a mini-DisplayPort, so you may need an additional adapter.
Make sure your computer and television are both turned off. Plug the DisplayPort end of your adapter into the Mac. Plug the HDMI cable into the other side of the adapter. Plug the remaining end of the HDMI cable into the HDMI port on your TV.
Turn on your TV set first, then power up your Mac. The Mac will recognize it is connected to the TV and in a few seconds, the output from your Mac screen will appear on the television. Make sure the TV is set to the correct HDMI channel. If the TV is set to the wrong output, you won't see anything.
Correct problems with resolution by referring to the owner’s manual for your TV. If some of the Mac’s display is clipped off on the TV screen, it is called "overscan." If you see black borders around the Mac screen display, it is called "underscan." Many HDMI TVs are capable of making quick, scan-related adjustments. You can also make manual adjustments on your Mac, although this will affect the Mac’s display when it is not connected to the TV.