Wires can lead to Death
In contemporary wiring, individual wires are run in a sheathed cable or conduit. The white/blue wire is neutral and the green wire is ground wire. The "hot wire/' is usually black or red, and they are dangerous to touch. To protect from electrical shock, learn hazards associated with basic wiring, and take steps to avoid these hazards.
Never attempt to handle any wires or conductors until you are absolutely positive that their electrical supply has been shut off. Properly lock out and tag all machines/equipment/circuits to prevent accidental startup.
You will receive an electrical shock if a part of your body completes an electrical circuit by touching a live wire and ground, or touching a live wire and another wire at a different voltage.
Consider all electrical wires as "hot" or "live" until verified as safe by a qualified person.
If you come in contact with an energized wire—and you are also in contact with a grounded path-current will pass through your body. You will receive an electrical shock.