There is a common WiFi attack that can disconnect any device on the network you are currently on. It also works on networks that you are not currently on.
How it works
There is a protocol in WPA2 that lets you disconnect a device safely from a network. However, these packets are not encrypted, so anyone with a WiFi-enabled device (like the ESP8266) can fake these packets.
Installing the software
First, go to the ESP8266 deauther page and download the latest release and download the file esp8266_deauther_[VERSION]_NODEMCU.bin.
Next, download the ESP8266 Flasher and run the utility. Flash the binary file (the .bin you downloaded) at 0x00000. Click Flash and wait till it completes.
Running attacks
On a device, connect to the Wi-Fi network named pwned and enter the password deauther. Next, go to the IP address 192.168.4.1 and click I have read and understood the risks and choose a target network. Under the Attacks tab, begin the attack Deauth.
A note on WPA3
WPA3, which was passed as an official WiFi protocol, encrypts these packets so hackers cannot abuse them. However, some WiFi routers still use WPA2, so this attack will still work sometimes.