Raspberry Pi

Raspberry Pi 2

What's a Raspberry Pi?  It's a small $35 computer board that works like a full sized computer.  There are a lot of similarly priced microprocessor hobby boards out there, but you have to program them down to bare metal to do anything with them.  By "bare metal" I mean they don't have an operating system that does the heavy lifting for you, allowing you to use keyboards, mice, monitors, storage, and other devices without having to write drivers to do anything useful.  This thing couldn't be simpler.  Power it using a simple cell-phone charger into the microUSB port and uses a small microSD card for storage after you simply download and copy the operating system onto the card, and plug it in. Plug an Ethernet cable into it, the HDMI output into an existing monitor or HDTV, and borrow a USB keyboard and mouse to get started.  Once you're up and going, you can set it up with a WiFi adapter into one of the USB ports and remote into it (running it "headless"), not tying up a monitor, TV, keyboard, or mouse thereafter.

Why, you might ask?  Think about all the software and projects you'd like to try that you don't want to mess up your primary machine up with.   And wouldn't it be nice to have a computer that only uses a few watts, and with no moving parts, that can be left on 27/4, indefinitely?   OK, it will set you back a few bucks if you don't have a spare reasonably powerful cell phone charger, and you'll probably want to sink $5-$15 into a case for it.  And $10 for a WiFi USB nub, if you don't have an old one around you can't spare.  But that's it.  With a WiFi nub installed, you could hide it in your sock drawer with only a USB cable hanging out.  Hell, run it from one of those USB cell phone charger battery packs, and you won't have even a cable poking out from your sock drawer.

So what do you get for $35?  How about a quad core 900 MHz floating point ARM processor with an integral 1080p graphics coprocessor, 4 USB ports, and an Ethernet port.  Audio and several discrete and serial I/O lines, if that's what you're into.  Yes it can stream HD video and it can be used as media server.  It can be a web server, TOR relay, and Email client or server.  Or in my case, a radio controller and signal decoder.  Or a surveillance camera appliance, detecting motion from a webcam and uploading it to your Dropbox account.  Yes, you can surf the web with it.  The default operating system even comes with a Microsoft Office clone (LibreOffice), a couple of programming languages, a nice desktop GUI, and even a few over the top programs: Mathematica and Wolfram Alpha.  Download more programs if you like, or modify others written for bigger machines, using on-line tutorials and videos.

With its default operating system (Raspian) it's a robust Debian Linux general purpose desktop using cheap cell phone chips and technologies.  You can do a lot more with it than you can with Windows 10 (which you can load onto it by the way, but please don't).

I have an original Pi (single core, half the memory, only 2 USB ports) that I've dedicated to a single purpose, and I recently bought the version 2, described above, still at the same $35 price for general learning and amusement.  They even sell a $5 stripped down version that you can embed in your projects.

For more information, go to:  https://www.raspberrypi.org/