Define A Computer

What even is a computer?

A computer is an electronic machine that takes information and uses it in some way. The information it uses is called data, which the computer receives through inputs. Types of inputs can include your keyboard, mouse, camera, and more - anything that send signals from you to your machine can be considered an input. What a computer does with those user inputs is a series of actions called processing. These are completed by the central processing unit, or CPU, which is a chip inside your computer. The actions the CPU takes are dictated by a set of instructions called a program. The output is the ending result of the CPU acting upon the input with instructions from the program. Outputs can be anything from speaker sounds to new display items to a robotic arm moving.

Input/Output, Programs, Data, and Processing are the basic building blocks of your computer. Your CPU can do many functions, but only with the help of these basics. In the primitive computer model, programs are stored in the memory of a computer. We'll go into more detail on memory later, but for now, the memory is simply a way to store information for short- and long-term.

Let's talk more about how a computer is set up. We'll go into more detail in further topics, but here's the basic components to a computer:

The User (that's you!)

Hardware

Software

Data

The User is simply anyone who uses a computer - the human behind the machine is more powerful than the machine itself. When Users come into the conversation of technology, there's a lot of things that directly affect them that we need to be conscious of. Not all Users are the same - Administrative permissions, security clearances, skill level, and knowledge are all concepts that changes how a User may behave and interact with the digital world. You may find you can do more at home than you can on a work or school machine - this is on purpose. Locking other users out from altering settings on a public machine is crucial to protecting data, software, hardware, and even other users.

Hardware is every physical part of your machine. Can you touch it? It's hardware! Even the CPU and other chips inside your machine count as hardware, but only in their physical components. Hardware comes in 4 categories: Input, Output, Processing, and Memory. These may seem similar to what we were discussing before - these hardware pieces hold all the internal data needed for your CPU to run programs and process data!

• Input Hardware is typically a peripheral (like a keyboard or mouse) that is plugged into the machine to allow the User to send data to the computer. However, this is not always the case - a phone's touch screen is also considered an input hardware.

• Output Hardware is additional devices (like a monitor or printer) connected to the machine that allow the computer to interact with the User and show outputs of processed data. A robotic arm when attached to a computer is considered an output hardware.

• Processing Hardware takes care of all the core functions of your computer. The central processing unit (CPU), the Motherboard (the main circuit board for your machine), and graphics processing unit (GPU) are all examples of processing hardware, as they take data and use programs to create outputs like displays, sound, and more.

• Memory Hardware are physical devices capable of storing information temporarily, like RAM (random-access memory), or permanently, like ROM (read-only memory). We'll go more into what both of these do in the "Parts of a Computer - Hardware" lesson.

Software is the programs and other operating information on your computer. These are usually digital systems that run INSIDE the hardware electronically. Software comes in 3 categories: System, Utility, and Application.

• System Software is the most crucial part of your system. This category includes your operating system (ie. Windows 10, macOS, iOS, and Android) which manages the computer's memory, processing, programs and more.

• Utility Software is the supporting role for system software and performs specific tasks to keep the computer running. Always running in the background, examples of utility software are security and optimization programs. Security programs include anti-virus software that scans and removes viruses. Most computers will include some sort of anti-virus software, but you can add your own. Optimization programs can include tools for system clean-up, disk defragmentation, and file compression. These tools are typically installed as part of the operating system. They have access to the hard drive to keep it tidy.

• Application Software is everything else! Anything outside those last two categories is an application or app. Word processors, spreadsheets, web browsers, and graphics software are all examples of application software, and they can do many specific tasks.

Data is the core information of your computer. It's how it reads inputs, creates outputs, and holds programs. Data in a computer is stored as binary data, where every file consists of a series of 1s and 0s called bits. 8 bits make up one byte, which is the basic unit of data storage. If you've downloaded a program before, you may have seen the file size - either in KB or MB or GB or even TB - and these sizes are all representative of how many bytes a program is. Kilobytes (KB) are made every 1000 bytes, Megabytes (MB) are 1000 Kilobytes, Gigabytes (GB) are 1000 Megabytes, and Terabytes are 1000 Megabytes. There are bigger sizes even past this, but for most average computing and storage, most people won't exceed 20 terabytes in their lifetime (personally as someone invested in tech, I only have to worry about 2-5 TB of data).

These basics will the foundation for your future learning. Knowing these concepts will help you build your knowledge into more advanced topics.

When you're ready, let's move to the next lesson.