When your Raspberry Pi arrives, you’ll see it’s a circuit board, about the size of a credit card, with components and sockets stuck on it. In an age when most computing devices are sleek and shiny boxes, the spiky Pi, with tiny codes printed in white all over it, seems alien.
It’s a big part of its appeal, though: most of the cases you can buy for the Raspberry Pi are transparent because people love the look of it. There are two versions of the Raspberry Pi: the Model B (which was released first) and the Model A.
The differences between the two are that the Model B has two USB sockets (whereas the Model A only has one), the Model B has an Ethernet socket, and editions of the Model B released after October 2012 contain twice the memory (512MB, compared to 256MB on the Model A and the first batches of the Model B). The Model A sells for $25, whereas the Model B sells for around $35.
The Raspberry Pi was made possible in part by the advances in mobile computer chips that have happened in recent years. At its heart is a Broadcom BCM2835 chip that contains an ARM central processing unit (CPU) and a Videocore 4 graphics processing unit (GPU). The CPU and GPU share the memory between them. The GPU is powerful enough to be able to handle Blu-ray quality video playback.
The creators of Raspberry Pi have stripped costs to the bone to enable you to own a fully featured computer for about $25–$35, so you’ll need to scavenge or buy a few other bits and pieces.
I say “scavenge” because the things you need are exactly the kind of things many people have lying around their house or garage already, or can easily pick up from friends or neighbours. In particular, if you’re using a Raspberry Pi as your second computer, you probably have most of the peripherals you need. That said, you might find they’re not fully compatible with the Raspberry Pi and you need to buy replacements to use with the Pi.
This is an edited extract taken from Raspberry Pi For Dummies by Sean McManus and Mike Cook, published by Wiley. It is on sale for less than £10 from Amazon.