This is the first lesson in a series introducing 10-year-olds to programming through Minecraft. Learn more here.
A computer is a collection of components. Each component has (at least) one responsibility that fits into four general categories: input, processing, storage, and output.
Input: Any object that can give the computer information can be considered input. The most common methods are via keyboard and mouse, but touch screens, microphones, and even network cards provide input.
Processing: Although this is handled by physical objects, they are not usually components you see very often. In today’s computers, processing is shared between the CPU (which handles the majority of ‘normal’ processing) and GPU (which usually deals with graphics).
Output: Generally, objects that generate something we can physically see and touch are considered output. Most of the output we get from a computer comes from the monitor, followed by printers.
Storage: Storage could be considered a form of output, but although storage itself is a physical media (e.g. hard drive, USB stick), we require a computer to actually access what’s stored; compare this to ‘output’ where it was something a human could see or touch (like a piece of paper from a printer).
How do we use a computer?
Everything discussed in the previous section is referred to as ‘hardware’: something that you can physically see and touch. The other part of what makes a computer work is ‘software’: the programs that tell the hardware what to do.
Operating Systems: The first ‘layer’ on top of the hardware is the operating system, or OS. You are probably quite familiar with Windows as one, and your iPod or iPhone run another one called iOS. The operating system is responsible for telling the hardware what to do for all four responsibilities. For example, the OS tells the hardware…
- what to display (output)
- what keys a user presses or what mouse button they pushed (input)
- when to store something on a hard drive (storage)
- what computations need to occur (processing)
Operating systems also tend to come with applications, which is really how most people communicate with their computer.
Applications: Minecraft is an application. You use your mouse and keyboard to move your character around the world, while Minecraft translates your inputs into commands that the CPU and GPU process (e.g. crafting an item), which results in output that you see on your monitor (a new item). Everything you do in a world is being saved to some form of storage, which allows you to continue playing when you re-join rather than having to start over from scratch every time.
Besides games, there are some other common types of applications that you or your parents might use: word processors for writing documents (e.g. Microsoft Word or Pages), spreadsheets for performing calculations (e.g. Excel or Numbers), and slideshows for presentations (PowerPoint or Keynote).
As developers, we create the applications people use on their computer. Modding (which we’re going to do with Minecraft) is modifying an application to change its behaviour in new and interesting ways.