For most people the inner workings of a computer are actually pretty alien anyway, regardless of whether they are in a desktop or laptop, so I will cover the basic's first before we look at the differences between the two. It is actually very simple when you break it down into it's constituent parts, and it makes rather a lot of sense. In other words it's very logical, as a computer should be:
- I am sure many of you will have heard the term CPU or Processor before. CPU is actually the more correct term, as their are technically two Processor's in your computer. The CPU is the "Central Processing Unit," it deals with everything that involves a lot of number crunching. When you double click, the CPU is the chip that interprets what you have done and then executes a program or command accordingly so that the system does what you asked for. Whether that be opening a file or running a program. It's one half of the brains of your computer!
- What many people may not have come across is the GPU or "Graphical Processing Unit," this guy is like an artist painting a constant picture that is forever changing. The GPU deals with anything visual in your system; you plug your monitor into the GPU output when you are using a Desktop. Computers without GPU's would be pretty boring, as they would pretty much display purely text based User Interface's. Here's where it gets slightly complicated. The GPU could be in one of two places depending on the hardware that's in your computer. Most modern day processors contain integrated graphics, there is a GPU embedded in the CPU. Essentially one big chip is doing both the CPU and GPU's work. We have seen this before on the blog in the Raspberry Pi. Usually integrated graphics aren't that powerful and can't stretch to very graphically intensive processes such as high quality games and rendering packages. However some chip's called APU's (Accelerated Processing Unit - From AMD) are available that contain a powerful CPU and GPU in one unit. Most likely your system does not use integrated graphics and instead uses a separate GPU. These tend to be more powerful as they are specifically designed to complete the task of being a GPU, rather than just being a small part of the CPU.
- You may have also heard of RAM or Random Access Memory. RAM actually comes in many different types and generations. However in essence it is just like the rough notes page you might use in a Maths exam; it's where the Processing Units do their working! Both your CPU and GPU have RAM, GPU RAM is called VRAM and CPU RAM is just called RAM. As I said before there are different types of RAM such as DRAM and SRAM, they each have their own benefits (Price vs Performance).
- The Motherboard is extremely logically named, much like the rest of the parts in a computer! It is the piece of hardware that ties everything together, like the towel you sew all of your swimming award patches too. Without it nothing would work. It can also perform other functions, such as provide IO to the CPU such as USB and Ethernet. Some motherboards even have integrated Wireless Cards, etc.
- Storage Drives are the places where all data that needs to be stored more permanently is kept, for example where you install Windows or keep your video's and photo's. There are two common types of storage, Hard Drives and Solid State Drives. Like RAM each different type has it's benefits. Solid State Drives can transfer data at higher speeds, but they cost a lot more money. Hard Drives are slower at data transfer, but they can store a lot more information for a much cheaper price. Of course cloud storage is becoming an ever more present contender in the file storage market. It may be the case in the future that they only local storage you have is your operating system.
- The power supply is fairly self explanatory, is is the thing that supply's power to the whole system. It provides many different voltage levels as different components need different amounts. A high quality power supply is one that has very reliable components and is very efficient. It needs to be reliable because if the power supply dies, it will very likely kill every other component in your system.
It is important to note that there are other accessories that can be added to systems using cards that slot directly into the motherboard. These can add functionality such as wireless connectivity, bluetooth, audio, etc.
So now you know what's in a computer, we can look at what the difference is between a laptop and a desktop! As I said previously in it's simplistic form there is no difference. Rather it is how the hardware is implemented that makes the difference and why your laptop can be so small, for example. As always it's more fun with a practical example! The video below will take it from here!
See you next time, for something particularly special!
Sam