Do camera lenses only work with certain cameras?

I keep on seeing camera's say that they are compatible with "this line of lenses" or things like that. But i have an old 35mm non-digital camera and I have tons of different brands of lenses! So i was wondering if the camera's now only work with the same brand lens, for instance Canon with Canon lenses or Nikon with Nikon lenses, etc.

No, there are still third party lens makers out there. SIgma, Tamron, and Tokina all make lenses for multiple mounts.

Even the lenses you have were not necessarily made by the company named on the lens… Sears is an example of a company that didn't actually make lenses, they paid companies like Cosina to make them and put the Sears name on them. That still goes on as well.

Depending on the lens mount of your gear, it may be possible to use it directly on a modern DSLR, or it may require an adapter to do so. If you can use it directly (Pentax K or Nikon F) then all you need is a camera. If your lenses use any other mount, like Canon FD or any maker that no longer exists (Konika for instance) then you are better off just getting new stuff. Sucks to buy all new gear when you have perfectly good old gear, but that's the breaks.

Canon lenses are for Canon cameras and Nikkor lenses for Nikon cameras. But there are Tamrons and Sigmas to fill the differences between the two. Tamron for Nikon, Tamron for Canon, Sigma for Canon, or Sigma for Nikon.

Nikon and Canon have enough line up of lenses for your needs so you don't have to worry.