One topic you might hear people discussing when they're talking shop about computers is how much random access memory (RAM) they need to add to their computer. Up to a point, adding RAM will normally cause your computer to seem faster on certain types of operations. RAM is important because it eliminates the need to "swap" programs in and out.
When you run a program such as a word processor or an Internet browser, the microprocessor in your computer pulls the executable file (.exe) off the hard disk and loads it into RAM. Large programs like Microsoft Word or Excel use large amounts of memory. The microprocessor also pulls in a number of shared dynamic link libraries (DLLs) -- shared pieces of code used by multiple applications. The DLLs take many more megabytes.
Then the microprocessor loads in the data files at which you want to look, which might total several megabytes if you are looking at more than one document or browsing a page with a lot of graphics. So a big application can easily take 100 megabytes of RAM or more, which can slow your system down significantly if there isn't enough memory.
How Much RAM Do You Need?
It's been said that you can never have enough money, and the same holds true for RAM, especially if you do a lot of graphics-intensive or data-intensive work. Next to the CPU itself, RAM is the most important factor in computer performance. If you don't have enough, adding RAM can make more of a difference than getting a new CPU!
If your system responds slowly or accesses the hard drive constantly, then you need to add more RAM. If you are running Windows XP, Microsoft recommends 128MB as the minimum RAM requirement. At 64MB, you may experience frequent application problems. For optimal performance with standard desktop applications, 256MB is recommended.
The amount of RAM listed for each system above is estimated for normal usage -- accessing the Internet, word processing, standard home applications and light entertainment. If you do computer-aided design (CAD), 3-D modeling/animation or heavy data processing, or if you are a serious gamer, then you will most likely need more RAM. You may also need more RAM if your computer acts as a server of some sort (database, application, FTP or network).