Is There Really a $5 Computer?
The Raspberry Pi Zero is “a $5 computer”, a credit card sized programmable computer that launched with $5 price tag in 2015. 
That truism points to a bigger point, as technology progresses, some computers ultimately get cheaper and smaller. The $5 Pi therefore represents the “fruits” of this trend.
On this page we take a look at the Raspberry Pi (including the zero model), check to make sure it meets the definition of a computer, and discuss some of the cool things you can do with a $5 Pi (or £4 Pi depending on your currency).
NEW Raspberry Pi Zero – $5 Computer!
TIP: The Raspberry Pi Zero is a fascinating step forward in affordable programmable computing. That said, it isn’t the only “tiny, affordable computer.” See a $9 computer that raised money on Kickstarter for example.
What is a Raspberry Pi?
A Raspberry Pi is a tiny affordable computer that, despite its size and simplicity, can do practically anything any other computer can do.
More specifically, a Raspberry Pi is a type of Single Board Computer consisting of one or more microprocessors. It can store data in memory, has built-in input and output (I/O) functionality, and has all of the parts of a desktop computer embedded in a single circuit board (a computer chip).
What is the Difference Between a Raspberry Pi and Raspberry Pi Zero?
A Raspberry Pi and Raspberry Pi Zero are both the same basic concept, a single board with I/O, and plugins. But Zero is a stripped down and slower model. There are a few different Pi devices out there; the high-end is the Model A+ (a variant of the 1st Pi), but a more comparable model to the Zero is the Model B.
If we compare a Raspberry Pi Zero to a Raspberry Pi 2 Model B ($35 -$40 retail), then we see some noticeable differences. The Zero only has three ports (one USB On-The-Go port for data, a micro USB port for power, and a mini HDMI slot for display), it has less RAM (512 for the Zero versus 1GB for the B), and it has only one core processor. On the plus side, the single processor has more CPU than a Model B and more “utility” than an A+. 
All this to say, the Zero can do most of what the other Pi’s can do, but it does so slower and at a smaller price point.
What is a Raspberry Pi Good For?
A Pi can work as an inexpensive replacement for a wide variety of computing devices, with a little time, money, and energy invested into buying and building. Some Pi devices have more uses than others. The more complex and CPU intensive, the more you’ll need to use the high-end Pi over the cheaper ones. See 25 fun things to do with a Raspberry Pi. Find out what people use Raspberry Pis for on Reddit.
Just Bought A Raspberry Pi? 11 Things You Need To Know – MakeUseof YouTube.
A Raspberry Pi is a “low cost, credit-card sized computer that plugs into a computer monitor or TV, and uses a standard keyboard and mouse”. – the official Raspberry Pi website
FACT: Raspberry Pi! What is it good for? Absolutely everything (almost). Now that you know what a Pi is let’s hit some check-boxes and make sure we can truly call the $5 Pi a $5 computer.
What is the Difference Between a Raspberry Pi and a Desktop PC?
There are three main differences between a Raspberry Pi and a more standard type of desktop PC (Personal Computer) peripherals, processing power, and price:
- Peripherals – A peripheral is a non-essential functionality, usually for input and output, or sometimes for making a computer more powerful or usable. In desktop or laptop computers, most of these peripherals are built into the computer itself. In a Raspberry Pi, only the most basic, “barebones” peripherals are included, and the rest are available as hardware extensions that you can buy and plug in.
- Processing Power – A Raspberry Pi has less processing power than most standard personal computers. However, most users don’t need (or use) the full processing power of their computer. This is especially true for Raspberry Pi’s intended audience; students (both adults and children) with little access to computer science education.
- Price – While a desktop or laptop computer can cost anywhere from hundreds to thousands of dollars, a Raspberry Pi usually costs less than $50. Believe it or not, most recent model – the Raspberry Pi Zero – is priced at only $5. You can get a full-fledged computer for less than the price of a meal at your favorite fast-food restaurant.
What Makes a Raspberry Pi a Computer?
Wikipedia defines a computer as follows:
A computer is a general purpose device that can be programmed to carry out a set of arithmetic or logical operations automatically. Since a sequence of operations can be readily changed, the computer can solve more than one kind of problem.
By the above definition, a Raspberry Pi is, without question, a computer – it can be programmed in a variety of programming languages. In fact, Ruby, C, C++, Python, and Scratch all come pre-installed on all Raspberry Pi devices.
However, Wikipedia’s definition is general enough to include devices that we wouldn’t typically think of as “computers,” such as mechanical analog computers and even Charles Babbage’s Differential and Analytical Engines (which are, arguably the first computers ever invented).
To avoid getting caught up in this abstraction, let’s take a look at other the similarities which make Raspberry Pi’s similar to the personal computers of today:
- Raspberry Pi devices use a standard desktop Operating System. Specifically, it’s most popular operating system is Raspbian – a variant of Linux/Unix. The OS X operating system that all Mac computers use is also a variant of Unix.
- Raspberry Pi devices support a wide variety of software programming languages. In addition to the defaults mentioned above, the devices also provide support for BBC BASIC, Perl, and Squeak Smalltalk, and others.
- Raspberry Pi can connect to the rest of the world. It has full networking (the internet, FTP, etc.) capabilities and can handle video and audio input and output.
- Each Raspberry Pi model has a CPU and a GPU embedded in the chip. In fact, the more recent Raspberry Pi devices have multi-core processors like those found in modern desktop and laptop systems.
- Raspberry Pi devices can run external software. Since they run standard operating systems, they can also run software developed for those operating systems. That means that you can run downloaded programs like games, web browsers, word processors, music players, other computer applications all on Raspberry Pi.
So, even outside the “abstract” definition of what a computer is, a Raspberry Pi can do pretty much everything a standard personal computer can do. By practically all accounts, a Raspberry Pi is, in fact, a computer.