Introduction
The Raspberry Pi Zero W extends the Pi Zero family, the Pi Zero W has all the functionality of the original Pi Zero but with added connectivity, consisting of :
802.11 b/g/n wireless LAN
Bluetooth 4.1
Bluetooth Low Energy (BLE)
Like the Pi Zero, it also has
1GHz, single-core CPU
512MB RAM
Mini HDMI-compatible and USB On-The-Go ports
Micro USB power
HAT-compatible 40-pin header
Composite video and reset headers
CSI camera connector
Addon Board
The USB addon board can connect the test point on the back of the Raspberry Pi Zero , then when you plug it to the USB on the computer , you can connect to the Raspberry Pi Zero via USB Ethernet without any other devices.