Mirrorless cameras have appeared on the photographic equipment market for a long time and in recent years, in terms of their characteristics, they have come as close as possible to SLR cameras. Therefore, when choosing a camera, you should pay attention to both types of cameras, and in order to understand the advantages of each of them, you should know how they differ.
If you put any two cameras next to each other, a SLR and a mirrorless, then only one difference will immediately catch your eye - this is the difference in size. Some mirrorless cameras are smaller and lighter. This is achieved due to the absence of a pentaprism, focus sensors and a mirror inside the housing. Also, most mirrorless cameras lack a viewfinder.
In SLR cameras, the light flux passing through the lens hits the mirror, reflecting it into the pentaprism, which, in turn, reflects the light into the viewfinder. Autofocusing is carried out using special sensors, on which light falls from an additional mirror. At the time of shooting, the mirror rises, blocking the viewfinder, and the light flux enters the matrix.
The structure of a mirrorless camera is much simpler. The light flux passing through the lens enters the matrix directly. From it, the image is transmitted in real time to the LCD monitor.
Each type of camera has its own pros and cons associated with the structural features. In short, mirrorless cameras are more compact, more reliable, cheaper to manufacture, but they consume battery faster, which, by the way, is less than in DSLRs due to the desire to minimize size. Also, focusing on mirrorless cameras tends to be worse and slower.
Mirrors, in turn, are less reliable, more expensive to manufacture, and of course they are larger. Although this has its advantages: they fit better in the hand and more controls can be placed on the body.