The Raspberry Pi family can be broken down into the "original" Raspberry Pi, the Raspberry Pi "plus", and the Raspberry Pi 2. Each of these designations also come in two flavours - Model A and Model B (with the exception of the Raspberry Pi 2 at present). The following table summarizes some of the differences between the different Raspberry Pi boards. I have not included the Raspberry Pi Compute Module in this comparison, as it's designed for embedded integration.
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