What is a ring main circuit in the UK and the Irish Republic?

A ring main circuit for example is:

key:

circuit breaker=0

cable=----

socket=[]

bends in cable=/ and \

Using the key this is a demonatration.

0---[]-----[]-------[]------[]---[]---\

\---[]-----[]-----[]----[]-------[]---/

Just imagine that there is only 1 circuit breaker in that circuit, both ends of the ring main should link up to that 1 breaker.

A radial circuit consists of just 1 cable going to the circuit breaker with sockets on the cable but there is no return path on a radial.

A ring main is just like a big circle with 2 ends of cable and sockets around the circle=both ends of the cable linking to the circuit breaker.