All camera systems offer a dizzying selection of lenses.
focus on what you plan to shoot
Less expensive lenses will generally have variable apertures
all major camera and lens manufacturers offer a variety of focal lengths to satisfy most budgets.
More expensive lenses have a fixed aperture
Wide angles give an expansive view
Wide angles are also handy in tight areas, like small rooms, cars, caves, etc
wide-angle lenses have the potential to drastically change your photography
Standard zoom lenses are great walkaround lenses
standard zooms tend to cover moderate wide-angle focal lengths all the way down to a medium telephoto
prime lenses offer just one focal length, such as 35mm, 50mm, or 85mm
So a standard prime falls somewhere in that 35mm to 85mm standard range
the most popular standard lens was a standard prime: the 50mm
a prime does force you to think more about composition and point of view, simply because it can’t zoom
And prime lenses also tend to be cheaper than optically-equivalent zooms
Telephoto lenses get you close to a subject without actually approaching them
The most popular telephotos seem to be various flavors of 70-300mm or 70-200mm
zooms allow you to stand back when the subject isn’t quite as approachable or when your subject might be feeling overwhelmed by the presence of the camera
lenses also compress distance, making everything appear closer together, as opposed to wide-angle lenses, which distort perspective and make things look separate.
lenses are also excellent for sports, nature, and wildlife photography