USA Mains Plug
Looking end on
Many appliances are are un-grounded and use a two-wire power cord and a simple 2-pin moulded plug.
Two-pin plugs, sockets and extension cords are usually polarized - the smaller pin is the power 'hot' (live) and often brass coloured. The 'low' (neutral) side is the larger white-metal pin.
USA and European Mains Plugs
The introduction of more stringent FCC rules concerning EMC radiation and NEMA safety regulations has resulted in an increasing use of 3-pin plugs and 3-wire power cables.
Grounded Plug -
looking at the blades. An easy way to remember polarity:
Brass pin/screw = Black wire [Hot]
White pin/screw = White wire
Green pin/screw = Green wire

Usually moulded onto Cable
Black = Live [Hot]
White = Neutral [Cold]
Green = Earth [Ground]
Same rules apply for cable selection as the UK standard loads for cables
D i s c l a i m e r
Whether you're starting a fresh or a competent electrical person, be sure to read and study the following pages, however if your not sure please contact sparky@homewiringguide.com or consult a qualified electrician, it's better safe than sorry -
Don't forget - Electricity KILLS....