Chapter 1. Getting Started with Raspberry Pi

According to the definition on Wikipedia,

The Raspberry Pi is a series of small single-board computers developed in the United Kingdom by the Raspberry Pi Foundation to promote the teaching of basic computer science in schools and in developing countries..

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The Raspberry Pi hardware has evolved through several versions that feature variations in memory capacity and peripheral-device support.

All Raspberry Pi versions have been using Broadcom SoC, including BCM2835, BCM2836 and now BCM2837.

For more info, please refer to https://en.wikipedia.org/wiki/Raspberry_Pi .