It can control physical devices like switches, LEDs, solid state relays (for really big power control), etc. It is used in controlling everything from lights to thermostats to robots. Lots of add-on kits available for it.
Just add keyboard, mouse and monitor (or TV). For $35 you can experiment with it and not worry about losing a lot of money. Or you can just play games and watch Youtube videos on your bigscreen TV!
Power is from a USB cell phone charger, so it can run on 110 / 220 volt power. You can take it on the road and plug it into hotel TVs and using WiFi have your own internet linked computer.
It has 4 USB ports, Ethernet port, audio jack, HDMI (TV), solid state memory port, camera port, etc. The most interesting is the input / output bus. You can program the pins to send / receive data, turn on / off devices, etc. There are free programs available to run stuff around your house (ex: "Jarvis" ala "Ironman").
We bought it as a kit. Turns out that is unnecessary (lesson 1). It is not too bad to configure. We chose the "raspbian" operating system which is free. It's UNIX based so it's a bit more technical than say windows, but still not bad. Lots of help online. Lots of free software also. Everything from games to serious scientific stuff.
This is a Pi 2. The newest model 3 has build in blue tooth and wifi. And it costs the same!
WARNING: Warning: mis-wiring or mis-programming your Pi or miswiring of accessories can ruin the Pi and accessories.
Information/drawings offered as is. Use at your own risk. If you don't know, learn first.
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