Alternating Current can be earthed since it will flow into earth. So, 'Earthing' is more commonly used with Alternating Current circuits. Direct Current will not flow unless the circuit is completed.The common route for completing the circuit is usually called the 'Ground'.

As I have said above, I believe it is basically a US/UK distinction, which is corroborated by the US McGraw-Hill Dict. of Sci & Tech Terms and the UK Chambers Sci & Tech Dictionary which BOTH give the "other" term as the usage in the other country.

That said, "ground" is (or may be) said, I believe, in BOTH countries in the case of what is also called the "mechanical earth" aka "frame earth" aka "frame ground", i.e. the connection of a circuit in a machine, car (?), etc. to the chassis or frame. I don't think the distinction is one of AC/DC: an AC machine can be "grounded", i.e. connected to the frame which is in turn "earthed/grounded to earth", but there will be two conductors carrying the current that makes the machine work, and they will ideally be insulated from the grounded/earthed frame. You will thus (in US parlance) find a distinction between "frame ground" and "earth ground"! I suspect the corresponding UK distinction is "earth" and "mechanical/frame earth".

In a car, for ex., on the other hand (DC circuit), circuits are completed by means of a connection to the chassis ("grounded", though here too "earthed" is standard in the UK). Cars are not physically earthed, of course (too much rubber on the wheels; unless you have one of those straps dangling down to discharge static electricity).

Cars can also cause you to be grounded when Dad won't let you take his car out to perfect your own layman's understanding.

Just checking in to try and clear up some of the misunderstanding surrounding these terms, caused mainly by 'woolly' use by techies.
There is NO distinction between 'earth' and ground' except linguistically between AE and BE. Both are usually translated as 'terre' in French
On the other hand, 'chassis' (sometimes 'frame', but less often) DOES make a technical distinction.
To simplify things, think of a simple circuit powered from a 12 V battery; a common convention is that the 'power rail' is regarded as +12 V, and hence the negative battery teminal becomes regarded as the 0 V [nought volt] rail (of course, there are other possibilities!)

Now this O V rail MAY be connected to the metal chassis of the equipment; this then means that the ) V rail also becomes the chassis connection, or earth rail.

In turn, it is possible that this O V rail may be literally externally connected to 'real' earth --- perhaps via the mains supply 'protective earth', or maybe even via a local 'earth spike'

So the distinction that needs to be made is between 'earth/ground', which properly speaking OUGHT to mean 'literally connected to the Earth' and a common return connection to the chassis of a piece of equipment, colloquially referred to as 'earth/ground', but with possible inaccuracy, since the chassis 'earth' may in fact be 'floating' and NOT at all connected to 'real' earth --- this is commonly the case in sensitive signal circuits, like audio equipment, where multiple earthing has to be avoided.
If you have any breath left, contact me privately if you dare for a longer exposition on the subject :-))

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Note added at 1 hr 56 mins (2004-07-13 10:50:43 GMT)
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Properly speaking, \'chassis\' is referred to as \'masse\' in French, so you will find \'masse reliée à la terre\' ---> grounded chassis.
But just as in English, fuzzy usage abounds!

Opps, just realized this was EN monolingual --- sorry!

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