The odds are good that you have resilient flooring -- sheet vinyl or vinyl tile -- somewhere in your house. After all, it's the most popular flooring material for kitchens, bathrooms, and laundry rooms. It's popular because it's easy to care for. And that's good for you.
This is not to say that a vinyl floor won't ever have problems. It is fair to say, however, that most serious vinyl flooring problems are not problems with the material itself. For example, if you have a series of ridges in your floor, you actually have an uneven or swollen underlayment. If your vinyl tile or sheet vinyl is coming up in places, you probably have moisture in the subfloor from a leaking pipe, spillage from the sink, or condensation from below.
As tempting as it may be, you can't just cover up problems -- you have to fix their underlying cause. Fortunately, this can be done without having to pull up the vinyl.
If the vinyl has black, brown, or purple stains that are visible just below the surface of the vinyl, there is no way to remove the stains without removing the vinyl. These stains are mildew and fungus that are being fed by moisture from the crawlspace, basement, or concrete slab or from water leaking beneath the vinyl. If you've got moisture under your floor covering, you've got to find the source and stop it.
Once you solve your moisture problem, you can then deal with the stained vinyl. If the damage is widespread, you unfortunately need to rip up the vinyl and underlayment (a layer of plywood or particleboard that is used as a smoothing layer on which the vinyl is laid).
This is an excellent opportunity to inspect the condition of the subfloor and refasten it to the floor joist using construction screws to eliminate current and future floor squeaks. If you do the easy fix instead of the right fix, you better like working on your hands and knees -- you'll be fixing the floor again and again.
With that said, there are a few things that you can do to keep your vinyl flooring looking good on a day-to-day basis.