If you have a newer MacBook, you may be able to quickly identify your ports by clicking the Apple icon at the top left of your screen, then choosing About This Mac. On the line starting with “MacBook Pro”, look for any information about the ports on your computer.

HDMI ports look like trapezoids. DisplayPort ports look like a rectangle with a corner cut off. USB-C ports are small and ovular. VGA ports have 15 small holes with a larger screw hole on each end. They’re often blue in color. [2] X Expert Source Luigi OppidoComputer & Tech Specialist Expert Interview. 31 July 2019. DVI ports have 24 small holes with a slit on one side.

HDMI ports look like trapezoids. DisplayPort ports look like a rectangle with a corner cut off. USB-C ports are small and ovular. VGA ports have 15 small holes with a larger screw hole on each end. They’re often blue in color. [2] X Expert Source Luigi OppidoComputer & Tech Specialist Expert Interview. 31 July 2019. DVI ports have 24 small holes with a slit on one side.

HDMI ports look like trapezoids. DisplayPort ports look like a rectangle with a corner cut off. USB-C ports are small and ovular. VGA ports have 15 small holes with a larger screw hole on each end. They’re often blue in color. [2] X Expert Source Luigi OppidoComputer & Tech Specialist Expert Interview. 31 July 2019. DVI ports have 24 small holes with a slit on one side.

To determine what type of adapter you need, compare the ports on your MacBook and monitor. For example, if your MacBook has USB-C ports while your monitor has HDMI ports, try searching for a USB-C to HDMI adapter.

If your monitor is not displaying your MacBook’s screen, be sure that you have selected the right video input. You should be able to change your monitor’s input by pressing a button on the bottom or the side of the monitor, selecting Input, then selecting the option with the same name as the port you are using. If your connecting cable and adapter are fully plugged in and you have checked your monitor’s input, but you still are not seeing your MacBook’s screen, your MacBook might not be detecting the monitor. For any operating system before Monterey, try opening System Preferences, choosing Displays, then selecting Detect Displays (you may have to hold down the Option key for this button to appear). HDMI cords create an instant digital connection. [3] X Expert Source Luigi OppidoComputer & Tech Specialist Expert Interview. 31 July 2019. Make sure the VGA port is turned on if you’re using a VGA connection. There’s usually a symbol on one of the “F” keys resembling 2 boxes with a slash between them. Hit the function key and then the corresponding “F” button to turn the port on. [4] X Expert Source Luigi OppidoComputer & Tech Specialist Expert Interview. 31 July 2019.

To switch between these settings, press Display Settings…, then select your monitor from the sidebar. Next, find the “Use as…” menu and choose either Extended display or Mirror for Built-in Retina Display.

You can determine what display you are looking at by hovering your mouse over it and reading the name that appears.

If you want to use your laptop as your primary display, you do not need to change anything.

If you are using an older version of macOS, go to Displays, choose the Arrangement tab, then check the box marked Mirror Displays.

If you are using an older version of macOS, go to Displays, choose the Arrangement tab, then check the box marked Mirror Displays.

If you are using an older version of macOS, go to Displays, choose the Arrangement tab, then check the box marked Mirror Displays.

If you are using an older version of macOS, go to Displays, choose the Arrangement tab, then check the box marked Mirror Displays.