What is a memory leak anyway? The concept doesn't make sense to me, something that keeps RAM from refreshing?
Yea, that's part of it. A memory leak occurs when an application grabs memory to use, and then doesn't release it when it's done with it. Worse, it doesn't reuse that block of memory, and just grabs another block when it needs more memory, and so on. Eventually, it uses up all the available RAM, causing the system to slow down as it starts paging, or crashing the app or system completely.