There is a lot to consider when it comes to figuring out how much memory your computer needs. To start with, it helps to understand what memory is. Memory for a PC is a bit different than how memory works in the human brain. The technical term for memory on a computer is RAM. Basically, the more memory space your computer has, the more applications it can run at once. Other than hard drive space, RAM is the most important factor in computer performance and speed. One cool thing about computers, unlike the human brain, is that RAM can be upgraded to match your growing needs.

For modern computers, you will want to start with a minimum of 1GB of RAM, and depending on the level of use and equipment, can be upgrade to 16 plus GB. Unfortunately, there is no one-size-fits-all answer to the question: how much memory do I need? The answer is dependent on several factors, including what operating system you're using, and what you're using the computer for. The needs of a casual Internet browser is going to be different than the RAM needs of a hard-core gamer, web designer, or video editor.

For casual PC use, 1GB to 2GB of RAM should be sufficient. Casual use includes Internet browsing, and running email and music applications. With smaller RAM, the user may experience lag when running several applications, or browsing the Internet with multiple windows or tabs open. The 2GB to 4GB RAM capacity would be better suited for users who prefer to have several tabs and windows open. This amount of memory is also better for word processing, flash games, watching videos, and simple graphics programs.

Students and heavy PC users would be better suited with 4GB to 8GB of RAM. This amount of memory is necessary for intensive multitasking, gaming, photo and video editing, as well as more complex graphics programs to run smoothly. More memory, in the 8GB to 16GB plus range, is only really necessary for professionals and hard core gamers. Modern PC games, multimedia editing software, graphic design, and 3D modeling software take a high toll on RAM. High-definition video also tends to play more smoothly with more memory.

The operating system of a computer is also important in determining how much RAM you need. Each operating system has a minimum requirement for memory to be able to run, as well as the recommended RAM for smooth running. It is always better to go with the recommended memory to avoid frustrating lag and applications crashing.

2GB to 4GB is recommended for Mac OSX Leopard and Snow Leopard. However, the newer Mac OSX Lion runs best on 8GB of memory. 1GB to 3GB of RAM works best with Microsoft Windows XP Home, while Windows XP Professional runs better with 2GB to 4GB. If you're running Microsoft Windows Vista 32-bit, or Windows 7 32-bit, 4GB of RAM is recommended. 4GB to 8GB is recommended for Microsoft Windows Vista 64-bit, and Windows 7 64-bit for optimal performance.