RAM is where data is stored while you are using it. It is a big chip inside your computer that is plugged directly onto the motherboard.
RAM is also refered to as "memory". Don't confuse this with hard drive, it's completely different! I will use the term memory for the rest of this article.
There are 3 types of data stored in memory - user data, programs, and cache.
1. User data consists of things that cause us to use computers in the first place - like documents, music, and pictures. The words you are reading right now are stored in your memory. Most user data is relatively small so I'm not going to talk any more about it.
2. Programs are the instructions that make it possible for us to work with user data. A program is the middle-man between the human brain and the computer's logic "brain". Programs can be many times bigger than the user data they are helping us with. The program I am using the type this document with is using about 138,434,000 bytes of my memory right now, while the document itself is only using about 7,000 bytes! This is because the program has SO many features, like spell check and word wrap and a bunch of pretty icons in the toolbar at the top, along with hundreds of features that you never notice and take for granted, like the ability to send data to a printer and the ability to write the document to disk when you "save" it, and the ability to unload itself from memory when you "close" it with the X in the top right.
Today's computers can run many programs at the same time. This is called multitasking, and it requires a lot of memory to pull this off. The more programs you run, the more memory it uses. Computers have a list of programs that run every time you turn the computer on. Most of these programs run in the background like chat messengers and anti-virus and programs that make your peripherals work properly such as cameras and printers. A fresh clean install of Windows 7 is going to have about 35 programs running in the background which uses about 350,000,000 of memory! These programs are critical for windows to function properly and cannot be disabled without messing something up. Any programs you run after the computer is started, like Word, Excel, or Internet Explorer uses more memory.
Some programs, like QuickBooks and Microsoft Office and Adobe Reader, have become so bloated due to lazy programming that customers complain about how long it takes for them to start up. Instead of fixing the program where it is less bloated and faster, they add the bloated parts to the startup list where it loads the bloat into memory every time you turn the computer on. This makes the program appear to load faster, but the computer boots slower. The bloat then remains in memory even if the user never runs the program.
To check your computer's memory usage and how many programs are running, click start, run, and type taskmgr (without the quotes). Then click performance. Here is what one of my computers looks like:
The first thing to look like is green number I have circled in red. I call this your memory usage. Mine shows 287 MB. The higher your memory usage is, the slower your computer will do everything. Memory usage is not to be confused with hard drive space. Memory is memory. The more programs that load bloat every time you turn your computer on, the higher your memory usage will be. The second thing to look at is your total physical memory, mine shows 1,037,416. Physical memory is on a computer chip inside your computer and costs money to upgrade.
Sometimes I see computers that are using more memory than they have. This is possible because your computer uses what's called a virtual memory, which I will talk about at the end of this article. Look at your task manager again, your physical memory is measured in KB, and the memory usage is measured in MB. There are roughly 1,000 KB in a MB, so I have roughly 1,037MB of memory, and I am using 287MB. How close is yours? Are you using more than you have? Now look in the bottom left of task manager, this shows you how many programs are running, mine shows 34. The lower this number is, the faster your computer will be.
To decrease your memory usage, you have to tell your computer not to start as many programs every time you turn it on. Windows XP and 7 come with a very easy program for this. Click start and run, and type msconfig (without the quotes). Now click startup. This is a list of programs that start every time you turn your computer on. You can uncheck the programs you want to disable. Don’t be shy, you can’t mess it up. I usually click "disable all" then enable what I want. The more programs you disable, the faster your computer will be. If you don’t recognize what something is, you don’t need it, and there probably won’t be many programs you will recognize. If you disable something that you later discover you need, for example the buttons on your printer that allow you to make a copy, you can simply run msconfig again and enable the program related to your printer. When you are done, click OK and it will ask you to reboot. After it reboots you will see a reminder that you have modified your startup settings, you can click the box that says dont show me this again. The last thing I want to point out, is upgrading your software will not speed you up. I know it sounds stupid, but the newer the software is, the slower it is. Dont believe me? Pick your favorite program, and search google for the recommended hardware requirements for different versions. You will find the newer it is, the more cpu, memory and hard drive space are recommended. I'll use Microsoft Word as an example.
cpu memory hard drive word 97 40mhz 8mb 46mb word 2000 75mhz 16mb 147mb word 2002 133mhz 24mb 265mb word 2003 233mhz 128mb 350mb word 2007 500mhz 256mb 1500mb
3. Cache - last but not least! This is most important to speed. If your computer hasn't used all it's memory up with user data and programs, it does something very useful with the extra. When the computer reads data from the hard drive, it keeps a copy of that data in memory, in a special section called the disk cache. If the computer needs to read that same data again, it will read it from memory instead of the hard drive. Since the memory is like 100 times faster than the hard drive, this is means that not only will that read request take 1/100th as long, but it leaves the hard drive free to read other data that's not yet in the cache, and that is the magic of the disk cache my friend!
This disk cache grows to fill all extra memory. This is OK because if the computer needs more memory for user data or programs, the disk cache will automatically give up some of its space to whatever needs it. When the cache gives up space, it gives up the data that was requested the least, so that the data requested the most can remain in cache. That's slicker than a soap makers butt if you ask me.
What you want is plenty memory for the disk cache to store all it can, and this is achieved by making sure user data and programs consume as little as possible.
If the user data and programs consume ALL the physical memory, the disk cache will cease to exist, and all data will have to be read from the hard drive, which results in a very slow computer.
You can buy more physical memory for your computer but 32bit versions of windows are limited to 3.5GB of memory, and 64bit versions of windows inherently consume more ram, and thus are slower, so I usually recommend 32bit windows for speed. It's best to use the memory you have more efficiently than it is to keep adding more. Also, the more physical memory you have, the more likely there will be a memory failure, which causes serious computer problems. 2GB is plenty for most computers. I run 3.5GB in my main computer.
If user data and programs grow bigger than the amount of physical memory in the computer, the computer will use what's called virtual memory, which works exactly opposite of the disk cache. Virtual memory is a file on the hard drive that pretends to be physical memory. So that spell checking dictionary will have to be read from disk after every word you type, and since the disk is about 100X slower, your computer will not be any fun to use, but this is better than getting an "out of memory" error, and not being able to do something.