A monitor arm attaches to your desk or wall and lets you adjust the height, angle, and position of your monitor. Most support one monitor, but some support two or more. A monitor usually does not come with an arm, so you have to buy it separately.
Monitor arms have many positives and nearly zero downsides. They provide a wide range of adjustment for height, tilt, and swivel, and many also pivot the display 90 degrees into portrait orientation. Monitor arms are also perfect for multi-monitor workstations. They also let you use your desk like a desk and take up less space. However, monitor arms can be pricey and require installation.
A quality monitor arm is comfortable to use, especially for multi-monitor workstations, and allows you to use your desk more effectively. The price and installation may seem intimidating, but a monitor arm is worth it.
Further reading: The best monitor arms
