The Raspberry Pi is a credit card sized computer originally developed with the intention of teaching coding to children. Since being commercially available in 2012, Pi has been in huge demand from enthusiasts around the world. The value-for-money has been the selling point for the Pi. At around $40, Pi offers a very affordable development platform for DIY enthusiasts to try their hands at implementing their ideas without breaking their bank. With the recent introduction of Pi Zero, and Pi Zero W into the market, Pi also offers an extremely cheap option in the sub $10 segment.
The original Raspberry Pi had an ARM based SoC from Broadcom with 700MHz CPU clock frequency and 256MB of RAM. In comparison, the most powerful Pi released till-date, the Raspberry Pi 3, has a Broadcom BCM2837 SoC sporting a four 1.2 GHz, 64-bit ARM cores, and 1GB RAM.
The Raspberry Pi Foundation releases a custom distribution of Linux called Raspbian that can be run on the Pi. The current version of the aforementioned distribution is called Jessie and can be downloaded from here. The OS is installed on a micro SD card and inserted to the slot on the board that is provided for this purpose. Follow instructions on this page to set up your memory card with Raspbian.
Raspberry Pi Models
Pi 3 :
The Pi 3 is the latest in the series of full-sized Pi. From the original Pi that offered 256MB of RAM and 700MHz CPU clock, Pi has evolved into a more that decent configuration with 1GB RAM and a four core 1.2GHz CPU on the Pi 3. You can get your hands on one here(Amazon DE/Amazon UK).
Pi Zero :
Pi Zero W :
Get a Pi Zero W including the development kit here.(Amazon UK/Amazon DE)