Electrical Grounding
Definition
Connecting a circuit or appliance to the Earth so stray electricity has a safe escape path instead of going through you.
Technical definition
A low-resistance reference connection to Earth potential (defined as 0 V). It provides a fault-current path that trips breakers and clamps exposed metal to safe voltage during faults.
Example
The round third prong on a US plug connects the appliance's metal case to ground. If a frayed wire touches the case, current rushes to ground and trips the breaker — instead of waiting to shock the next person who touches it.
Ground is not where current 'goes to disappear.' In a working circuit, current returns to its source through the neutral wire, not the ground — the ground wire normally carries nothing at all. Grounding is a safety backup, not part of normal operation; a GFCI outlet trips precisely because it detects current leaking where it should not be.