I was showing my friend how I had used my Raspberry Pi to make my TV “smart”. Right after seeing my setup he asked a question that I didn’t really know how to answer. “How does a Raspberry Pi Work?” Not wanting to leave him hanging, I did a little research and came back to him the next day. Here’s the best answer I could come up with.
How does a Raspberry Pi Work? A Raspberry Pi works similarly to most computers. It has a hard drive, a processor, ram, operating system, and some standard ports. What is different about a Raspberry Pi is the size, cost, and the exposed GPIO (General Purpose Input/Output) pins that allow you to connect to a wide variety of other devices.
The Hard Drive
Every computer needs a hard drive, a place to store information. Right now most computers have either a disk drive or a solid state drive. Disk drives are exactly what they sound like, a disk, similar to a DVD, that stores all of the computer’s information. Solid state drives are hard drives that don’t use disks. Instead they use a relay of electrical charges to store information.
Raspberry Pi’s use micro SD cards as their hard drives. While micro SD cards are technically a type of solid state drive, most users wouldn’t put them in the same bucket. They work in the same way but tend to be much smaller and are usually used for storing media files.
Processor and Ram
The processor and ram is the brain of a computer. The processor is what does the “thinking” and the ram is the “short term memory”. Like every computer, Raspberry Pi’s have both a processor and some ram. What is different than most computers is that these are built directly into the computer. In most computers, you can change the processor and amount of ram but this is not the case for the Raspberry Pi.
Another difference between Raspberry Pi processors and that of standard personal computers is the type of processor that is used. Raspberry Pi’s use ARM processors which are a little simpler in nature. These processors tend to be smaller and a little less powerful than those found in a personal computer.
The operating system is the primary software that runs on a computer. Most consumer computers run on either a Windows or Apple operating system. While those two are by far the most popular, there are other options that exist. For example, Google has created its own Chrome OS and also owns the Android OS.
Raspberry Pi’s typically use a Linux based operating system called Raspbian though this is not the only option. Linux is an open source operating system, meaning that the code is available to the public and can be contributed to by anyone. Because it is publicly available, it is also free to download and use, keeping the cost of Raspberry Pi’s lower.
Other free operating systems for the Raspberry Pi include Ubuntu, Windows 10 Iot, OSMC, LibreELEC, RISC OS, and others.
Like most computers, Raspberry Pi’s have a few connection ports that should look quite familiar. The power port is a micro USB, similar to that of many phones. There is also some form of an HDMI port on every version of the Raspberry Pi. Some models have USB 2.0, USB 3.0, micro USB, composite video, stereo audio, or an Ethernet port available as well. Along with the standard ports, many Raspberry Pi models also include wifi and Bluetooth capabilities, allowing them to be connected to devices and the internet wirelessly.
This is the first area where there is a major difference between a standard consumer computer and a Raspberry Pi. The total space taken up by a Raspberry Pi is less than 5in3.
The small size of the computer allows it to be used anywhere and everywhere. Due to it’s small size, the Raspberry Pi is perfect for making everything from robots to tablets.
The price point of the Raspberry Pi is what really put it on the map. While a standard consumer class computer can run anywhere from $200-$2,000, the sticker price of a Raspberry Pi is between $5 and $55.
Adafruit, the creators of the Raspberry Pi, intentionally keep the price as low as possible. It is their goal to allow programmers, engineers, and everyday tinkerers to make their ideas a reality without having to spend a fortune.
The GPIO or General Purpose Input/Output pins are what truly set the Raspberry Pi apart. Each Raspberry Pi has a set of exposed pins that can be used to read signals and control electrical devices.
The pins can be programmed to use a seemingly endless number of peripheral devices from electric motors to moisture sensors to touch screens to GPS boards. The flexibility of these pins is what lends the Raspberry Pi boards to being perfect for hobbyists.
Where can you buy a Raspberry Pi?
A Raspberry Pi can be purchased from a number of locations. Below is a short list.
Do you need to be a programmer to use a Raspberry Pi?
Not at all!
There are many step by step tutorials on how to set up a Raspberry Pi to use as a computer. However, if you want to get into more advanced uses then having a working knowledge of Python will be valuable.
What shouldn’t you use a Raspberry Pi for?
Raspberry Pi’s are very small and inexpensive computers. In order to keep the price low and the size small, the processor is not extremely powerful and there is limited ram and storage space. A Raspberry Pi is great for small projects but should not be used for advanced resource intensive computing.
A general rule of thumb would be that if your phone would have enough power for a project, a Raspberry Pi will too.
Update: The Raspberry Pi 4B with 4GB of ram is able to do many of the computational tasks of a standard personal computer.