This is the smallest Raspberry Pi SBC available at the moment. The board is just half the size of a Raspberry Pi Model A+, and has Bluetooth and WiFi onboard!
For most applications, 1GB of RAM is sufficient, especially if you have a specific application for the Raspberry Pi where little multi-tasking takes place.
This colour coded 2x20 male header is a great way to add pins to your Raspberry Pi Zero. The colour-coded GPIO pins make locating that ground or power connection you need super simple!