Okay, this is gonna be a looooooooong ramble, but hear me out. So I've been researching this stuff for around 5 to 6 years now, and with my electronics course now 3 years behind me, I can say I have some pretty solid ground in this area. So, since it was the first thing you asked, let's look at the pros and cons of computers and laptops for gaming. Starting with computers, the main pro is that computers are much, much cheaper, especially if you know what you're doing. If you don't mind snapping together a few parts like very expensive lego and giving up a good half-day's work to get everything looking great, then building your own PC is even cheaper than a pre-built gaming rig. Not only this, but because of their very open, manage interior, they are easy to upgrade, and it's easy to replace parts, allowing you moderate freedom to do what you want, even after you've finished the initial build. All that aside, desktop PCs generally run a lot better, since they rarely get moved and have little risk of being broken once up and running where you want them. Tip from experience here, don't ship one overseas. It's a big headache. So you've got customisability and integrity, but what else do you need? Performance, obviously. Now, I know gaming laptops and desktops are built for the same purpose so you'd think, and people do argue that performance isn't an issue, but the fact remains that in a laptop, the space is a lot more cramped, and heat is much harder to dissipate than in a desktop. This means higher cpu temperatures, leading to a drop in performance... Eventually. These days laptop coolers are very good, so the difference is negligible, but if you plan on using this extensively, you might begin to see a difference. But for someone always on the go to various tournaments events and whatnot, then a laptop might prove invaluable. It mainly comes down to what you wanna do. If you're gonna sit in your room and game a bit, maybe record videos or something, then a desktop will save you a ton of money and still bring you amazing performance. If moving around a lot for big gaming events is your thing, then a laptop is probably where you wanna look. Another little side-note here, building your own laptop is much more expensive than buying pre-built, so don't bother. By the sounds of it you're not overly in need of portability, so I would advise you to look at a desktop, since I imagine your budget is also somewhat limited (unless you're filthy rich in which case, boo, gimme money :P)
So onto the next bit, gaming rigs in detail. So, since you said you know very little, I'm going to explain from the very basics up, though I imagine you already will know some of what I'm gonna say, but maybe it'll still help in some way. A computer is built up of various different parts, which all work together in harmony to do the work you set them to do. How to choose your build really depends on what you want to do. If office related menial tasks is the case, then you can skip out on a dedicated graphics chip for example, but since your want is to game, then you'll be needing one of these. Your parts you will be looking at when choosing your build, either building yourself or buying pre-constructed, are as follows:
- CPU - The core of any computer and definitely not worth skimping out on. A processor is made up of cores anywhere between a single core and up to twelve cores. There are processors with even more, but those are not for gaming rigs. Each core has a thread which actually process commands. Although each core only has one thread, through an exploit such as Intel's Hyperthreading, the cpu can exploit idle stages in its activity, allowing the appearance of more cores to the operating system, allowing simultaneous actions to go through a single core. Because of this, more cores doesn't necessarily mean a better cpu. It's important not go too cheap on your cpu either, as a very cheap cpu may not be able to keep up with the work load, and may cause a bottleneck, inhibiting the performance of your gpu and other components as well.
- CPU Cooler - A lot of beginners, myself included, overlook the importance of a cpu cooler, and how it affects your build in the long run. Most CPUs will come with a stock cooler included, but this is rarely enough to keep your processor at an optimal temperature whilst working. Definitely not when gaming. As a processor attempts to thread more commands needed for games, it draws a little more power from your power supply. This in turn will increase the heat given off by your cpu. More work = more load on the cpu. Higher load = higher voltage requirement. Higher voltage = more heat. Therefore it is important to make sure that your cooler can keep your cpu from overheating and breaking during particularly intense gaming sessions.
- Motherboard - This is the bread and butter for a computer, and all of your components will work through this. Unless you have the right motherboard, you may find yourself stuck with something that can't house all of your components which you just paid a lot of money for. Motherboards come with various cpu, ram and pci sockets and it's important to know what your motherboard can support. A motherboard with a LGA1151 chipset will be able to support the newest generation of intel processors, however don't try and shove an AMD processor in there, because it's not going to work. Ever. Similarly pay attention to whether your RAM slots are DDR3 or DDR4 (or DDR2 if you're buying some super old pos), and make sure to buy the appropriate RAM, or motherboard if you've already decided on the RAM. Lastly the pci slots are where your external cards such as a gpu and wireless card will go. If your intention is to house multiple gpus, then make sure you buy a motherboard which not only supports two graphics cards in the form of two pci-e slots, but also supports SLI or Crossfire, depending on whether you bought an AMD or Nvidia gpu.
- RAM - This is the storage where all of your data will be processed before being saved and returned to the hdd. Too many people think that RAM is like an extension of the cpu to help in multitasking, and whilst ram certainly can do that, it's not because it's an extra bit of cpu power. No, RAM is where data gets stored when it is being used and worked on, to be faster called upon by the processor. RAM is much faster to draw data from than a HDD. Your operating system and any open programs will be put here, so the more space you have the more you can do, simply put. For most games 8GB is often recommended, so I would always suggest around 16GB to ensure you have room to keep a window or two open, and have space for your OS in the background. Of course, on a budget 8GB is fine, and I worked with that for nearly 5 years without issue.
- HDD/SSD - Your hard disk drive or solid state drive is where your data gets stored when it's not in use, or when the pc is switched off. Simply put, it's a car park for data, which the data must exit when it needs to be used (ie go somewhere) and where it gets returned to when it's no longer needed. RAM is like a waiting bay for data, which is much faster to pull up to and leave than a multi-story car park which is your hdd/ssd. SSDs are much faster than HDDs, but also much more expensive for large storage space. What I always have done is kept my OS and a couple of key games on my SSD, and had a large HDD for everything else, that way I have a low cost SSD to ensure my computer starts fast and can load games I play a lot very quickly, and a HDD for everything else I do, such as videos music and steam and so on.
- GPU - Your graphics card, when gaming, is what will handle everything that appears on your screen. This is your centre piece for gaming, and another area you really mustn't skimp on when building a gaming rig. Graphics cards can be joined in SLI to split the work load in two, but this is only useful really when gaming at very high resolutions or using something like Nvidia surround, which utilises multiple monitors to widen game views across all monitors i.e. Skyrim on three monitors. On two is just rubbish, don't bother. On a single monitor running at 1080p even an outdated card like the GTX 660 will run games at a smooth 60fps, although maybe not at the best quality of graphics nowadays. This is where, as an average gamer, you save yourself the $$$. More on that later.
- PSU - I nearly forgot this, good lord. Your power supply is the thing that will make sure your rig has enough power to do everything it says it can. There's not a lot to say about it, other than don't overpower your rig like I do. You don't need a 1000W PSU for a single card setup. Never in a million years. Maybe a double card setup. Thankfully I intend to do just that, but don't be a spoon and waste all that electricity. Usually a 750W will do everything you need and more, and will a budget build you can get away with a 550W with room to spare. There is a calculator online for this, so if you're really uncertain, you can just take a peak. As for choosing one... I would never ever go cheap on this. Corsair gold certified and above only for me, but other brands like cooler master and so on also have good rep. I'm just a corsair fanboy :P
- Case and Peripherals - Okay, so a lot of people tend to focus little on the case and lots on peripherals, but your case is super important with regards to keep everything inside it cool. With your case, you must also consider case fans, how they are aligned and what pressure you want inside the case. A positive pressure will mean more air gets sucked in than gets pushed out, and a negative pressure means the opposite. A negative pressure is ideal when you don't want to have to fuss very often about cleaning, as dust will get blown straight out as it comes in, but this does mean you sacrifice some effectiveness in cooling. Whereas a positive pressure again means the opposite. I'll talk more on cooling set-ups later. The peripherals are really personal taste, and come down to how you like your desk to look and what suits you. Also $$$.
So that's that. Now you're up to speed on exactly what you'll be taking into consideration, you need to decide; do you have the patience, time and desire to build yourself your perfect rig, getting exactly what you want, at a lower price but at the cost of hard work and potential damage if you do something wrong? Or can you afford the premium you pay for the convenience of having it built for you? Once you've decided, you can move forward with your planning. Either way, you need to look at what you want to buy for what you're doing. Casual gaming = cheap gpu, intel i3 (at most) 8GB ram and 1TB storage (roughly). If you wanna buy it built, then just pick either a gpu or cpu you've decided on and look for computers with that part. The rest of the pieces wont stray far from your wishes. If you wanna build it yourself then keep going.
Okay. So you wanna build your own PC. You're up to the task, ready to get hands-on and get some life experience that, imo, everybody these days should have. Building your own PC is easy. Like, really easy. You already know what you wanna do with it, so head off to pcpartpicker.com and start plugging in your pieces. The automatic compatability filter will make sure all your parts fit with each other, so piece a build together is easy. What imo takes a load of time is choosing a case to put it all in. Cases have various form factors and also various shapes through which air has to pass to cool your system. Planning this out is much more of a head-scratcher than one might think. Do you want a positive pressure or negative (positive is better in my experience, but you're going to be buying a couple of extra fans for that)? Where do you want the intakes and outtakes? Make sure to consider the surface your pc will be sitting on. I have the nzxt Phantom 530, with dual 140mm on the front as intake, a 120mm on the bottom as intake, a 140mm on the side as intake, dual 120mm on the top as exhaust, a 140mm on the back as exhaust, and a 120mm on the inside as air flow regulator, pushing the cool air over the gpu towards the back of the case, for an example. My psu draws air in from the bottom of the case, but beware, if your case doesn't have feet to raise it up, positioning your cpu fan down might cause your psu to overheat and burn out. Once you have settled on everything, go ahead and buy that stuff and when it arrives, DO NOT RUSH. This is how you break components. Rushing to dive in and get started will lead to oversights in preparation, and can lead to you building up static charge and forgetting to earth yourself, or simply breaking a component by being to rough. If your components arrive after school with homework to do, don't even think about starting that evening. Wait until the weekend if need be, set yourself a good half day, a full one if this is your first build and go slow. Before you begin, look for somewhere to regularly earth yourself. If you're on a carpet, make sure to buy yourself an earthing bracelet and attach this to any earthed surface, such as a radiator or copper pipe. Or if you have a large metal sink, you can always touch that regularly to ensure no static has built up. Don't wear socks is another tip for you. Now you can start with your case, open it up, look it over, read the manual, see exactly how to connect it all up before you've even touched the other parts. Next install all extra case fans you bought. Believe me, if you try and do that after you've installed your mobo and whatever, you're gonna have a real bad time. Make sure to check the directions of your fans, and just take your time. Line everything up square and nice, then move on to the next step. Water cooler radiator (if you have one) This is the next thing to install. If you don't have it, skip straight to the motherboard. Most cases come with motherboard offsets, but if they don't, make sure to screw in all offsets before mounting your motherboard. Contact against the case can lead to a short Circuit (eyyyy) which you really don't want after spending so much on it. Once that's finished, put your cpu in. Careful not to bend any pins, make sure it's secure, and now you need not worry about it. You can do your RAM next too, then the PSU. Start threading your cables through to the back of the case now, to save yourself some work. Utilise any cable ties you have, since cable management costs only a bit of work, and improves air flow and appearance of your build a ton. Next install the gpu and the storage devices, plug it all in and finally you should be about done... Unless I'm forgetting something. I don't think so... I'm getting old.
Okay. Moving right on now to the final part of this ramble which is my suggested build to you. It's not going to be the biggest, it's not going to be the flashiest, but it'll get the job done at a great price. If you don't want to use this, it's in a spoiler, so you can ignore it. If you have a bit more money to spend, you can refer to the price list Juno posted that I gave her, or just go ahead and find your own build. Nothing is more satisfying than finalising a build you constructed yourself... For me. I love doing this. My favourite hobby, albeit expensive. Anyway, here:
If you have any questions after this, feel free to ask away, though I might be slow replying. I hope this helps as a cover-all for the basics in gaming rigs and so on, and gives you a little insight to help you go away and try something yourself, without being completely clueless. I remember my first build I didn't even realise cable management was possible nor that it was necessary! I hope you have fun if you do decide to build yourself and I highly recommend it. The experience is invaluable. That does it for me, Aiden out!