First Computer

[Self-sain]

Alright so I am building my first computer, With no prior knowledge of this I think I'm getting the idea. Alright I have my mother board picked (MSI 890FXA-GD70 ), along with cpu (1100T Black Edition), I deiced I'm going to go/ get RAID level 5 , and I know I want a terabyte for my memory but I haven't actually picked one.

It seems like there are some savvy furs here, so I had thought I could ask some questions.

RAID
I understand what Raid is, but I'm not to sure how to "attain it" if you will. Like I understand that its multiple hard drives and how the computer transfers data and all that, but how do you exactly do this? 
Also do I need like a specific type/feature for my mother board to allow me to do RAID? Sorry if I'm way off, virgin waters here.
Would there be a point of getting a terabyte if I do some how mange to do RAID level 5?

Hard drive
(With this, I want to keep in mind the fact that I do wish to have RAID)
I know not all CPU's are compatible with all motherboards, is it the same with hard drives?
Also any good ones that are recommended?

Case and power supply
I'm beyond lost here  , any and all advice/recommendations would be nice.

Also... what is ram, I know its important but, how high do I need it so that my computer can be fast and smooth?

[Timmy Fox]

Hmm...

RAID I'm not too experienced with myself either, so I don't think I can help you out much on this...

Any harddrive nowadays should be compatible with nay motherboard as long as it's an SATA harddrive, which rather any consumer harddrive to my knowledge is.. Then however if you get a SATA III (6 Gbps) harddrive, I believe it should be fully backwards compatible with Sata II motherboards (ALL motherboards to my knowledge support this).
For recommendations, I'm quite happy with my 1TB drive from Western Digital, WD1002FAEX. Otherwise I've heard the Samsung Spinpoint F3's have gotten very good reviews as well, so you might wanna look that one up as well.

Case and PSU (Power supply)
For a case recommendation, I'm not sure what to recommend, but I am very happy with my current Fractal Design Define R3. It's sound isolating which makes it very quiet, cheap and has a nice design imo.
For power supply, it depends on how strong hardware you'll use (GPU's and such) but I suppose 650w-750w should be quite enough for the average rig. I recommend power supplies by Corsair.

RAM means Random Access Memory and is basicly the computers temporary memory. An average user shouldn't need more than 4GB, myself I use 8GB but that's because I do some more heavy video editing and such. But you should be fine with just 4GB. Tho since memory is really cheap, you could either always add more later or add a few extra bux for another few GB of RAM. But from my recommendation, 4GB should be enough. To be honest, it's possible to survive quite easily on just 2-3GB unless your actually planning to put some real stress on it. But just some games and some browsing should not require more than 4.
Also I would strongly suggest buying either 2GB or 4GB modules, less is just a waste. For 4GB is 2x2GB is the most widely recommended, but 1x4GB is more future proof as you'll get more free slots which means you can pack even more sticks in if you'd like in the future.

[Self-sain]

Thanks Timmy, such a helpful Fox

[Timmy Fox]

No problem, computers is my hobby, so I try to help as much as I can
As well I know how it was building my first own rig