- Accessories for cameras are mainly for care, protection, special effects and functions.
Lens hood: used on the end of a lens to block the sun or other light source to prevent glare and lens flare (see also matte box).
Lens cap: covers and protects the lens during storage.
Lens adapter: allows the use of lenses other than those for which the camera was designed.
Lens filters: allow artificial colors or change light density.
Lens extension tubes allow close focus in macro photography.
Flash equipment: including light diffuser, mount and stand, reflector, soft box, trigger and cord.
Care and protection: including camera case and cover, maintenance tools, and screen protector.
Camera monitor: provides an off-camera view of the composition with a brighter and more colorful screen, and typically exposes more advanced tools such as framing guides, focus peaking, zebra stripes, waveform monitors (oftentimes as an "RGB parade"), vectorscopes and false color to highlight areas of the image critical to the photographer.
Large format cameras use special equipment which includes magnifier loupe, view finder, angle finder, focusing rail /truck.
Battery and sometimes a charger.
Some professional SLR could be provided with interchangeable finders for eye-level or waist-level focusing, focusing screens, eye-cup, data backs, motor-drives for film transportation or external battery packs.
Tripod, primarily used for keeping the camera steady while recording video, doing long exposure and timelapse photography.
microscope adapter, an adapter used to connect a camera to a microscope to photograph what the microscope is examining.
cable release, a remote shutter button that can be connected to the camera via a cable to remotely control the shutter, it can be used to lock the shutter open for a desired period of time. It is also commonly used to prevent camera shake from pressing the built in camera shutter button.
Dew shield – Prevents moisture build up on the lens.
UV filter, Can protect the front element of a lens from scratches, cracks, smudges, dirt, dust and moisture while keeping a minimum impact on image quality.
Ref - https://en.wikipedia.org/wiki/Camera