An electrical service is typically anything that transmits or distributes electricity such as electric lights, wires or cables.
A non-qualified person can still carry out notifiable electrical work as long as Building Control are informed. If the work is then done to an unsafe standard you can be fined.
Your electrics should be inspected and tested every 10 years for an homeowner. If you rent a home it is every 5 years.
Electricians who do work on domestic premises in England and Wales must carry out the work to the standards of Part P of the Building Regulations.
Most households have a single phase meter connected to 230 volts or 240 volts via two wires.