Can the olympus 50mm F2.0 lens be inter changeable with other brands of DSLR cameras?

Can this Olympus lens be used on other brands of DSLR cameras?

The Olympus Digital Zuiko 50mm f/2 Macro lens, and any other Digital Zuiko lens is interchangeable with any Four-Thirds mount body.

Currently, Olympus and Panasonic are the only companies making Four-Thirds bodies. The lens cannot be crossed with any other system (Nikon, Canon, Pentax, Minolta/Sony, etc.).

Most manufacturers use a proprietary lens mount. Lenses made for other cameras are generally not interchageable.

You can't use Pentax lenses on a Nikon camera or Nikon lenses on a Pentax camera.

Some camera brands will share mounts, for example Samsung DSLRs can use Pentax lenses, and Fuji DSLRs will use Nikon lenses.

Actually, yes you can.

I sometimes use M42 (Pentax Asahi) and old Canon FD lenses with my Canon 5D. They key for connection is an adapter, of which there are two types: Regular adapter rings with no chip in them and the chipped ones. If you connect the Oly lens with a chipped ring onto say a Canon EOS you can even manually twist the focus ring (there was no auto-focus motor in the old lenses) until your autofocus point in the camera detects something forcused and then emits a beep. So you have semi auto-focus. With the regular type of adapter there are no electrical contacts and just connects the lens to the body. The chip type of sensors are more expensive.

Of course it will all be manual operation, you can use the camera's meter to judge the shutter speed. Aperture is controlled (as it should be) on the lens ring.

It would be a waste of good glass to disregard older lenses, some of it is wonderful. There is a whole subculture of manual focus lens on modern cameras, below are some links.

Just because the lenses are old, it doesn't make them cheap, especially the more exotic lenses.

You'll find that the many of manual lens users are Canon users because of the full format sensor of the 5D & 1Ds (until the D3 came along) because these lenses work wonderfully with a full format sensor (as they were made to do back in the day). There are many nikons (and other brands) mounted together with older lenses, but Canon is the most popular combination (I may be wrong - and not that it matters)

No.
Each dSLR (and in general SLR) manufacturer has their own mounts and their own electronics for a lens to operate. It's not possible to mount any lens to a body different than the one it's been made for....

The off-brands, like Sigma, Tokina, Tamron, etc. usually make several versions of their lenses with mounts for different bodies for this very reason...

LEM.