When a computer is started, it loads the programs needed to run the operating system and software into memory. As a computer is used, the operating system can fill up memory, requiring it to move the least used data from memory to a paging file on the hard drive or solid-state drive. This additional drive activity can significantly drop the performance and responsiveness of a computer. Having enough memory reduces the need for this activity and can almost completely eliminate the drop in performance. If productivity is important, max out the amount of physical memory in your computer. It may not be the least expensive component, but in most cases, it's the best way to get most performance from your investment.