Basic terminology. First off, what you are wanting to build is a desktop computer. This is basically a computer that sits on your desk (Easy enough!). Now, a computer consists of many components that make it work. It's much like a community that depends upon each other. Everything works together to make your OS run properly, along with all your software. An OS (Operating System) is like Windows or Linux. My guess is that you'll be installing Windows since you're at this forum . Now, what oldwolf was talking about with AMD and Intel is your processor. The processor is the primary chip of the system that oversees all the other components of the system. AMD is one manufacturer of the chip, while Intel is another. These aren't the only two, just the leading manufacturers. To get a little more complicated, there are two basically two types of chips. You have 32-bit processors, and you have 64-bit processors which are newer. Microsoft just recently released a OS that supported 64-bit. To make the difference betweent he two fairly simple think of it like this. 64-bit can push 64 bits of data, while 32-bit can push 32 bits. 64 is obviously greater than 32 so it's faster. Hopefully that makes a little sense. 64-bit was generally for servers, but nowadays it has become more mainstream and many users are starting to use the 64-bit. You can do a little more research to help you decide on what to choose, I'm just going over some basics. Somebody else can correct me if I'm wrong about the 64-bit and 32-bit and give a little advice on what to choose. Thanks! Moving along to where to put the processor. It is placed in the motherboard, which is the central or primary circuit board. The motherboard is where everything connects. It is the "mother" of the machine, hence it's name . There are many types of motherboards. Everyone is a little different. The first thing you'll have to do after deciding between an AMD chip or an Intel chip is to choose a motherboard that supports your chip. Most newer boards should support it, but if you're trying to save a little money you may want to buy an older one to save a bit of money, but still have support for the chip. The downside to this is that you will most likely have to buy a new motherboard in the future to support a new chip. It's a tradeoff. Do you want to save a little money right now, or do you want to be able to upgrade easily? The decision is up to you. Like I said, motherboards are all a little different. Here is some basic terminology. AGP (Accelerated Graphics Port) is where you insert your graphics card if your motherboard supports AGP. AGP is much faster than PCI (Peripheral Component Interconnect), I'll get to PCI in a bit. Some motherboards already have video on them and there is no need to buy a video card. This is called Integrated Video. Depending on if you are an avid gamer or not this is really up to you. If you play alot of games than I would get a motherboard that supports AGP and buy a video card. If you don't play alot of games than I would just get a motherboard with Integrated Video. If; however, you are a gamer you have basically two choices. The two leading graphics card manufacturers are Nvidia and ATI. Some individuals will tell you one is better than the other and argue it forever, but what I have found best is just testing both of them and see which performs better in my box. That's why I have an ATI in this machine and an Nvidia in my other machine ! You are wanting to buy though, so you're probably not going to be able to test what you are buying like I am. Now, if you go to Best Buy or someplace alike you will see a spot with all these different video cards and all these different numbers on them like 128 or 256. I won't go into great detail with this, but basically the bigger the number the more data it can push making it faster. If you are a gamer and want to be able to play many games that come out in the future get a 256. Onto what PCI is. Depending on your motherboard, you will have a different number of PCI slots on your board. These slots allow you to insert additional cards such as Network Card, Modem, video Card, Sound Card, Wireless Card, etc. The list goes on because there are many things that you can do with them. You may look at that and go "WHAT!?!" after seeing Video Card. You can get a PCI video card if your motherboard doesn't support AGP, but I wouldn't go that route. That's why I didn't really talk about it, just clearing that up. AGP is much faster. With a Sound Card, you can buy motherboards with On-Board Sound, but it's normally not the greatest quality. Also, if you have Surround Sound Speakers for your system you may want to buy a Sound Card that supports that. To answer your question about RAID and hardrives. RAID is an acronym for Redundant Array of Independent Disks. There are different kinds of RAID...RAID 3, RAID 4, and RAID 5. Think of it like this, you have more than one harddrive in your computer and you want to make sure that all your data gets backed up. So, by using RAID you can set it up to whenever it writes to your harddrive it writes the exact data to the other harddrive so you have an exact duplicate and if your harddrive goes bad, you have the second one to go to with all your data intact. Now the different kinds of RAID allow you to set it all up a little differently. For example, you can have 3 harddrives in a computer and setup your RAID to write 2/3 of the data to each drive. That way if one drive goes bad you can put in a harddrive to replace it and the other two drives each have half of the original drive that went bad. That way you can rebuild that drive and everything is peachy! This is used more-so in a sever setting so you shouldn't have to worry about it unless you want to make sure that everything is backed up. Back to the motherboard. You can buy a motherboard with Integrated Video, On-Bard Sound, as well as built-in network. That way you don't have to worry about a network card. i'm not sayign what you should do, I'm just telling you what you could do. I hope that helped a bit. If anybody reads this and finds an error please correct me. Thanks!