Still not sure what mirrorless cameras are? Here's how they compare to DSLRs

Many mirrorless cameras feature a digital viewfinder, which displays what the image sensor is seeing. This works a lot like an optical viewfinder on a DSLR, but you're looking at a small screen instead of a reflected image.

The digital viewfinder works similarly to the live-view feature found on many contemporary DSLRs. That feature uses a rear LCD screen to display what the sensor is seeing in real time.

Like DSLRs, many mirrorless cameras have a large LCD screen in addition to their viewfinders. So when you compose a shot, you have your choice of screens.

One advantage of digital viewfinders over the optical ones on DSLRs is that they will give you a pretty good idea of what the final shot will look like before you shoot it, taking into account your exposure settings in real time. An optical viewfinder, by contrast, will only show what the seen looks like to your eye.

The one big downside of a digital viewfinder is it weighs heavily on battery life. It takes a significant amount of energy to power the viewfinder's display, something you don't have to worry about with the optical viewfinder on a DSLR. As a result, the battery in a mirrorless system will typically drain faster than in its DSLR counterparts, at least when shooting still images.

When shooting video on a DSLR, you're restricted to using the live view mode on the rear screen. This can easily chew away at your battery if you're not careful.

Since mirrorless cameras have digital viewfinders, you don't have to eat away at your battery life by powering a large screen on the back of the device (although most mirrorless cameras do feature a rear screen that you can use for video if you want).

Therefore, if you're planning on shooting a lot of video, mirrorless cameras can have an upper hand when it comes to battery life.

The lack of internal mirror mechanics allows mirrorless cameras to be just as powerful as DSLRs, without the bulk. High end DSLRs can get quite large, which can be uncomfortable if you're carrying the camera around all day or wearing it around your neck.

When you press the shutter button on a DSLR camera, the internal mirror needs to flip up so the sensor can be exposed. This results in the iconic shutter sound that is ubiquitous with traditional photography.

There's nothing inherently wrong with shutter sound — it can actually be satisfying. But in some shooting situations, silence can be a huge benefit. If you're shooting at an event like a recital or somewhere a loud shutter sound would be considered rude, a mirrorless camera can offer you almost silent shooting, since there's no mirror that needs to be flipped.

We're still pretty early in the life of modern mirrorless technology, at least when it comes to DSLR-level performance. Thus, mirrorless cameras are inherently going to be pretty expensive. If you don't absolutely need a mirrorless camera, there's a pretty good chance you'd be better off buying a DSLR that performs just as well, but cheaper.

If money isn't an issue, however, mirrorless cameras are an example of exciting and promising new tech, and you probably won't regret the purchase.

Companies like Sony and Fujifilm got into mirrorless technology well before Nikon and Canon. Although it was slow to the punch, Canon introduced its EOS-R mirrorless system this year, and Nikon's Z mirrorless series just launched as well.

So if you're already invested in a particular brand's camera ecosystem, there's a good chance you can find a mirrorless option that will allow you to use some accessories like lenses. However, you'll likely need an adapter for your old lenses, as many new mirrorless cameras use a new lens mounting system.

For a full list of Sony's full frame mirrorless cameras, click here. For crop sensor cameras, click here.

Click here to visit Nikon's mirrorless store page.

Visit Canon's mirrorless store page here.

To see all of Fujifilm's X series, click here.

Although Nikon and Canon are two of the biggest names in photography, plenty of companies have been offering mirrorless cameras for a while now. B&H Photo offers a pretty comprehensive list of mirrorless cameras, available here.