VESA stands for Video Electronics Standards Association and they produce a bunch of standards related to video, monitors, etc but most people, when they say VESA, refer to the VESA mount or, more correctly known as Flat Display Mounting Interface. Long story short, it specifies how far apart the holes for screws should be on screens so that you can a buy a monitor and a monitor mount and expect them to work together. Sadly, we cannot have one single mount because we have both screens as small as 14″ all the way up to 50″ in the market and they have very different weights and mounting needs. But at the same time, it’s not really as complex as the Wikipedia page for it makes it look like. The vast majority of VESA mounts out there look like this:

It’s four holes, arranged in a square of 100mm in side. This is sometimes known as 100mm x 100mm for obvious reasons. The screws are obviously standard as well and in this VESA mount they are M4. You also have other arrangements for the holes, such 75mm x 75mm, 100mm x 200mm, 200mm x 100mm, 200mm x 200mm, 400mm x 200mm; but something like 98% of monitors models produced these days are in square 100mm with a few being square 75mm as well as others.

The monitor pictured above comes with a stand that looks like this:

which is not using screws but some clips/latches that, as far as I know, are not part of the VESA mount standard, but a convenience for assembly. If you buy a third party mount, such as a monitor arm, it will most likely look like this:

As you can see, it has the holes for square 100mm and square 75mm. It doesn’t hurt to add both even thought the smaller one will rarely be used. When you mount the monitor, it’ll look something like this (nowhere near as good as the factory stand, but hey! it’s a standard):

If you wonder how it would work with a square 75mm since the mount wouldn’t fit. Most monitor arms and mounts come with accessories to help you: little cylinders that make the plate hover farther away from the monitor:

For heavy weight mounts, those for big screens, you actually get mounts that can do all different sizes of VESA, such as this:

But those are very rare.

Of course, the exception to all of this is the Apple Cinema Displays, that from the back look like this:

There’s a VESA mount adapter for those that’s a bit tricky to install but what will be even more tricky would be to find monitor stands that can hold such a heavy screen.

Another interesting VESA accessory is the one that let’s you mount a laptop:

You would use that to mount your laptop next to your monitors when you are using monitor arms:

And that’s pretty much all you need to know about VESA. If you have any questions, please, use the comment box bellow and we’ll try to address it as soon as possible.