Wireless TXRX – ESP8266 (Serial Wireless Module)
In terms of the form factor, it looks a lot like the nRF24L01 2.4G RF transceiver. This is a serial module with a built-in TCP/IP stack, so you can use it standalone but you will be likely limited. You need a FTDI to connect this module to your computer, and start communicating with it. FTDI is a common name for USB-to-TTL (or serial) converter.