We often think of "solving a problem" in the sense of making it go away, so that the problem no longer exists. This indeed is one kind of solution, but it is not the only kind. Some problems cannot be eliminated entirely: we are never likely to eliminate trash, or the wear on automobile tires, or the occurrence of illness. We can, however, create solutions or treatments that will make each of these problems less harmful.

So it is helpful when thinking about a problem to define it in a way that some goals or parameters will be set that allow us to know when the solution is reached. Sometimes the goals might be that the problem is entirely eliminated and sometimes the goals will be to treat the effects of the problem.

There are two basic approaches to defining solutions:

Stop It	Cures the problem. This might be in the form of preventing it from occurring or re-occurring, eliminating it all together or reducing it to point where it is no longer defined as a problem.
Mop IT	Focuses on the effects of the problem. One can treat the damage, tolerate it, or redirect it.

(Robert Harris, 1998)