WiFi Module ESP8266(colour may vary)npm

2.4 GHz Wi-Fi (802.11 b/g/n, supporting WPA/WPA2),

general-purpose input/output (16 GPIO),

Inter-Integrated Circuit (I²C) serial communication protocol,

analog-to-digital conversion (10-bit ADC)

Serial Peripheral Interface (SPI) serial communication protocol,

I²S (Inter-IC Sound) interfaces with DMA(Direct Memory Access) (sharing pins with GPIO),

UART (on dedicated pins, plus a transmit-only UART can be enabled on GPIO2), and

pulse-width modulation (PWM).