Mirroless Camera - An alternate to DSLR cameras?

Whats DSLR?
DSLRs use the same design as the 35mm film cameras of days gone by. A mirror inside the camera body reflects light coming in through the lens up to a prism (or additional mirrors) and into the viewfinder so you can preview your shot. When you press the shutter button, the mirror flips up, the shutter opens and the light hits the image sensor, which captures the final image. Lets discuss about Nikon D3400 and compare it with mirrorless camera.  

Whats mirrorless?
In a mirrorless camera, light passes through the lens and right onto the image sensor, which captures a preview of the image to display on the rear screen. Some models also offer a second screen inside an electronic viewfinder (EVF) that you can put your eye to. Our example of a mirrorless camera is Sony's A6300.

 

Lets Compare them
Size & Weight: You can carry a mirrorless camera more easily and fit more gear, such as extra lenses, into a camera bag.
Autofocus Speed: Both types offer speedy autofocus, with mirrorless cameras offering hybrid sensors that use both phase and contrast detection on the sensor.
Previewing Images: For many situations, especially low-light shooting, the DSLR's optical viewfinder is better.
Image Stabilization: Image stabilization technology is largely equivalent in both camera types.
Image Quality: With equivalent sensors and image processors, both camera types can take great photos.
Video Quality: With superior autofocus in most models, mirrorless cameras provide the best results for most filmmakers.
Shooting Speed: The simpler mechanics of mirrorless cameras allow them to shoot more photos per second, at higher shutter speeds.
Image & Video Playback: Both types offer large screens and video outputs, and some offer Wi-Fi connections to smart phones for quick image-sharing.
Battery Life: DSLRs offer the ability to shoot without using the LCD screen or EVF, which can extend the battery life.
Lenses & Accessories: DSLRs offer access to the wider range of lenses, but the gap between the two types is narrowing as more mirrorless lenses become available.
Durability: Both types offer models that are hardened against the elements.

Bottom Line
Mirrorless cameras have the advantage of usually being lighter, more compact, faster and better for video; but that comes at the cost of access to fewer lenses and accessories. DSLRs advantages include a wider selection of lenses and better optical viewfinders.

For beginners, mirrorless cameras are often a better choice due to their more compact size and simpler controls. Mirrorless cameras are also more likely to have a touchscreens than a similarly priced DSLR as well. However, as you move up in price, the size difference between mirrorless cameras and DSLRs isn't as extreme, although mirrorless cameras still have a small lead. That said, unless there's a big need for 4K video, a serious or pro shooter who wants access to a wider range of lenses and other gear would be better off with a DSLR.