Tethering shares your smartphone's mobile data connection with other devices like laptops and tablets, effectively turning your phone into a portable Wi-Fi router when no Wi-Fi is available.
Three connection methods exist: Wi-Fi tethering (most common, connects multiple devices), USB tethering (stable speed, charges the phone simultaneously), and Bluetooth tethering (low power consumption but slower speeds).
Tethering consumes your phone's data allowance. Video streaming and software updates on a connected laptop can quickly deplete your data. Some carriers charge extra for tethering or impose separate data caps. Check your plan before using it.