Let's take a sample from a game on Steam... GTAV's minimum listed requirements for instance and take it piece-by-piece.
This is pretty much self-explanatory but this is what your computer "runs" at its most accessibly basic level. Windows 3.1, Windows 95, Windows 98, Windows XP, Vista, 7/8/10, etc. The basic idea here is that this is whatever you have for your computer to use as its "front page", so to speak. If you're not using anything at least as new as Windows Vista SP2, you're pretty boned with modern games (though a machine using Vista as a gaming platform would be...less than optimal). Service Packs are large, cumulative updates to the OS released by Microsoft. If you aren't updated to your Windows' most current service pack, you need to drop what you're doing right now and get it installed. Seriously, not joking.
The processor or CPU is the "brain" of the machine, as many love to use this analogy. It directs the system and keeps things running. As for how to read these entries? Well, I can't help you with the AMD side of things--that's not my area of personal interest. But I can help you with the Intel naming system.
The basic gist of reading the name of Intel processors is that they lead off with "Intel" as the brand name, then follow up with the model family of the chip such as "Core 2 Quad" (this was split up by Core 2 Solo/Duo/Quad/Extreme back then), put on the specific name of the chip "Q6600", and finally end with the performance rating or "speed" of the processor, "2.40GHz". If you want to think of in terms of vehicles: Ford Fusion Titanium 2.0L I-4 engine. Ford = Intel, Fusion = Core 2 Quad, Titanium = Q6600, 2.0L I-4 engine = 2.40GHz. Not quite the same but it's a basic analogy, deal with it (please don't be pedantic assclowns).
The Intel Core 2 entire family of chips have been replaced by Intel current name scheme by labeling them as Core i3 (analogous to the Core 2 Solo/Duo), Core i5 (Core 2 Duo/Quad), or Core i7 (Core 2 Quad/Extreme--the "Extreme" equivalents have a number with an "x" added to it, because adding an "x" to something's name makes it faster and cost roughly $200 more). If you want to put it in basic terms, i3 processors are basic no-frills CPUs, i5 are mid-level processors, and i7 are "enthusiast" level processors for overclocking or high performance demands. That Q6600 processor they list as a minimum requirement is actually a pretty old processor at this point, from 2007, but at the time, it was a pretty high end processor. Not the absolute highest but it was pretty beefy for the time and still viable today (though it's reaching its obsolescence point pretty soon).
As an example, my computer uses an Intel Core i7-930 2.80GHz. I can pretty quickly look at most requirements lists and know that my processor is somewhere in the middle or middle-high capabilities for running a given program. It's difficult to give advice on your specific computer's capabilities when I don't know them. I've given you as much information as I feel like writing out for analyzing it yourself however.
Well, Rockstar didn't go into much detail here but I guess it really isn't that necessary. RAM is the heart of the computer. Everything relies on it to keep things moving and to actively work. If you're curious about the finer details, there are better resources out there than some asshole on Reddit like myself.
As for the system requirements and how to read it... It's pretty simple. You need a system with at least 4 GB of RAM to run the game comfortably. Most modern PCs tend to sit somewhere between 4-8 GB of RAM. Enthusiasts might go higher, somewhere around 16 GB or even up to 32 GB (because "reasons"). Knowing more details about your RAM and its capabilities is something you would be best served asking about in /r/buildapc or elsewhere.
For this question of yours though, it's easier to just ask yourself: "Does my RAM have more GB than what they suggest?"
Hoo boy. Well, graphics is referring to your video card or GPU. Much like the processor entry above, the names have a specific scheme they tend to follow. And again like above, I'm an nVidia guy, not an AMD guy, so I don't know the specific voodoo that goes into AMD's wacky naming. But we can use the same general rules I listed above for Intel.
NVIDIA (brand name) 9800 (family name) GT (specific chip name from family) 1GB (general capability level of video card). Unfortunately, nVidia's naming scheme is fucking stupid because it follows some weird as hell rules that you simply can't know unless you get into it and research. As an example, my card is a GTX 660. But just so you know, that name means it's better than a GTX 750, even though 750 is a higher number. How do you figure this shit out? It's two factors: What are the last two numbers of the card's name and does it end with GTX or GT? It's roughly equivalent to the Core i3/Core i5/Core i7 stuff from nVidia.
Anything that ends with 20, 30, 40, or 50 and a GT tends to be on the lower end of the scale. 60, 70, and 80 tend towards the higher end with 90 being at the top end. TYPICALLY. nVidia like to do things like release special versions of the GPU that are overclocked or have slightly modified architectures for higher performance, appending a "Ti" to the end of the card's name to designate that. As a result, a GTX 660 is less powerful than a GTX 760 and that's less powerful than a GTX 960 and so on (an 860 doesn't exist--nVidia wanted to skip to the 900s because reasons). However, a GTX 660 Ti is equivalent to a GTX 760. And the GTX 760 Ti would be roughly on par with the GTX 960. BUT WAIT, THERE'S MORE! Want to see something really, really stupid?
GTX 590 = GTX 680 = GTX 770 = GTX 960, roughly. Yes, nVidia's naming system is FUCKING STUPID and there are WAY too many options. I don't know what card you use but it'd be easier to compare against that and tell you where you stand more than try to explain this dumbass system. Also, just so you know? There are also the Titan cards. Long story short: Titan < Titan Black < Titan X < Titan Z. I don't even want to get into explaining that stupid shit.
Got enough space on your hard drive(s)? That's all this asks. The specific capabilities and performance of the drive are typically not important though they'll affect how fast you load.
If you have a motherboard with onboard audio that has a modern CPU and GPU in it, you almost certainly meet this "requirement".