The Raspberry Pi is a tiny computer about the size of a deck of cards. It uses what's called a system on a chip, which integrates the CPU and GPU in a single integrated circuit, with the RAM, USB ports, and other components soldered onto the board for an all-in-one package.
It doesn't have onboard storage, but it has an SD card slot you can use to house your operating system and files. The Raspberry Pi is small, doesn't use much power, and is relatively inexpensive at just $35.
Raspberry Pi
The nonprofit Raspberry Pi Foundation originally designed the Pi as an inexpensive computer for teaching programming, but it quickly became popular among DIYers looking for a more powerful brain in their electronics projects.
Since its inception, many models of the Pi have been released, some with multiple revisions (like the Raspberry Pi 3 Model B+, which improved the previous Model B's networking capabilities).
The latest Pi, at the time of this writing, is the Raspberry Pi 4 ($66.00 at Amazon Canada) , which rocks a 1.5GHz quad-core ARM CPU, a 500MHz VideoCore VI GPU, and 1GB of RAM—though you can step up to 4GB of RAM for a bit more money.
Earlier models are still available for $35, but you can often find used models a bit cheaper than the list price. These older models produce less heat, which is a nice feature if your project doesn't require much power.
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