Looks like a late 90s BSO.
I also notice the boots/stanchions from the forks have rotted and dropped off. And that you're missing the front brakes completely.
Not only that, the front rim is completely missing a rotor and doesn't even appear to have a rotor mount. I suspect the front wheel was replaced at some point. As such, this bike is not safe to ride.
The suspension is a spring with a damper on the inside. The damper will be purely cosmetic and any damping capability will have long since vanished. I found that a 60 kilo teenage rider could over-compress the rear suspension making the whole bike extremely saggy to ride.
That frame shares a lot with this late 90s Raleigh RFX
UPSHOT If you have a disk front wheel, rotor, and spare working front caliper/lever already, it looks like a straight forward tune up. If you have to buy any more than cleaner and lube then think twice. Unless its sentimental in which case its your decision.