Raspberry Pi Model B Last week, the UK-based nonprofit Raspberry Pi Foundation announced the latest version of their popular Raspberry Pi computer. Dubbed "Model B+," it's the third model the organization has released to the public since Model A went on sale in 2012. Raspberry Pi, in case you're not familiar, is a computer about the size of a pack of playing cards and sells for around $35 (or less). Thanks to the Pi's low cost, simplicity, and extensibility, educators and do-it-yourselfers have been buying them up at times faster than the manufacturer can make them. For educational nonprofits, schools, and libraries, Raspberry Pi is very useful for teaching students about electronics, computing, and many other technical subjects for a price that's far less than a new computer. Libraries have also experimented with replacing terminals with smaller footprint Raspberry Pi computers. About Raspberry Pi The author with his Raspberry Pi Simply put, the Raspberry Pi is a computer. The whole thing is less than 3 1/2 inches wide, 2 1/4 inches long, and an inch tall. It includes a CPU, graphics processor, RAM, USB port (multiple ports in later models), audio and video ports, and an Ethernet port (later models only), and runs a Linux-based operating system. For a rundown on what all these components are, check out our hardware basics article. It doesn't include a hard drive, but instead includes a slot for an SD or microSD card. Anyone buying a Raspberry Pi for the first time will also need to get extras like a case, power cord, and more. Programming with Raspberry Pi The Raspberry Pi was designed to help educators and students understand technology better. Specifically, it's a tool to help students explore how hardware works, try Linux, and learn to program. Researchers at MIT have developed a program called Scratch , which is a unique way to help students learn to program. Students can create interactive stories, games, and animations to understand the basic concepts of programming before learning actual code. Beyond the basics, the RPi Hub at the Embedded Linux Wiki is a great resource for programming for Raspberry Pi. The hub has lots of helpful information on understanding Linux and how to write code for it in popular languages like C#, Java, JavaScript (via Node.js), PHP, Python, and more. Beyond Learning to Program The real beauty of the Raspberry Pi is its extensibility. Along with its standard connectivity, like USB, HDMI, and SD cards, the board also includes a "general-purpose input/output" (GPIO) circuit. Basically, this is a 26-pin (Models A and B) or 40-pin (Model B+) connector that you can use to plug in other electronic equipment. If you want to analyze sensor readings, project to a specific type of display, or use it for something really scientific, the GPIO makes it possible. A quick Google search of Raspberry Pi projects produces a long list of ideas. With the GPIO, programmers have made it possible to do everything from automate your home to feed your dog . For educators, though, there are tutorials and projects that are a bit more practical. Raspberry Pi Beginners takes you from opening the box it comes in to configuring it to starting basic projects. Adafruit also offers step-by-step guides for many fun electronics projects that feature the Raspberry Pi, and MagPi is a monthly magazine devoted to the latest projects that the community has developed. If you're looking for even more inspiration, here's a short list of other things you can build for educators: Temperature Monitor Source: Raspberry Pi - Temperature Monitoring by Findus238 / CC BY Humidity and temperature sensor (originally developed for brewing beer at home, but the concepts are universal) Weather station Robotics Digital camera Web server (LAMP) Measure weight Landline phone (PBX) FM radio Creating sounds Buying a Raspberry Pi Allied Electronics is the official US distributor of the Raspberry Pi. Currently, they don't offer the Model B+ yet, but you can purchase Model A ($25) or Model B ($35). There are plenty of other third-party retailers that resell the Raspberry Pi, too, of course. Note that those prices are for the computer only. It doesn't include anything else you'll need, like a case, keyboard, mouse, screen, power supply, etc. If you're starting from scratch, check out the bundles rather than the standalone computer. They tend to include other useful components like an SD card with an operating system pre-installed. Tutsplus has a helpful guide to buying your first Raspberry Pi, complete with info on every component you'll need. Some tips: Pick the Pi that best fits your needs. Need more RAM or USB ports? Check out the later models, which include 512 MB RAM. Look for an SD or microSD card that comes with an operating system preinstalled. You can always flash a card on another computer before transferring it to the Raspberry Pi, but buying a preformatted card may save you an extra step. Don't forget the accessories! The stock Raspberry Pi doesn't even include a case, so be sure to pick up all the extra components you'll need. Luckily, like the Pi itself, they're pretty affordable too. Full specifications on each model: Model A Model B Model B+ Board Broadcom BCM2835 SoC full HD multimedia applications processor CPU 700-MHz Low Power ARM1176JZ-F Applications Processor GPU Dual Core VideoCore IV Multimedia Co-Processor Memory 256 MB SDRAM 512 MB SDRAM Ethernet N/A 10/100 Ethernet RJ45 jack USB 1 USB 2.0 port 2 USB 2.0 ports 4 USB 2.0 ports Video HDMI (rev 1.3 & 1.4), Composite RCA (PAL and NTSC) HDMI (rev 1.3 & 1.4), Composite video via 1/8-inch jack Audio 1/8 inch jack, HDMI Storage SD, MMC, SDIO card slot microSD OS Linux Peripherals 26-pin GPIO 40-pin GPIO Dimensions 3.4 inch x 2.1 inch x 0.6 inch 3.4 inch x 2.1 inch x 0.7 inch 3.3 inch x 2.2 inch x 0.7 inch Power ratings 300 mA (1.5 W) 700 mA (3.5 W) 600 mA (3.0 W) Power source 5 V via Micro-USB What About You? Have you experimented with a Raspberry Pi? Log in to tell us how you used it in the comments.