The Road Traffic Act, 1933 requires all drivers of mechanically propelled vehicles in public places to have at least third-party insurance, or to have obtained exemption – generally by depositing a (large) sum of money to the High Court as a guarantee against claims. In 1933, this figure was set at £15,000. The Road Traffic Act, 1961 (which is currently in force) repealed the 1933 act but replaced these sections with functionally identical sections.
Soon after the introduction of the Road Traffic Act in 1930, unexpected issues arose when motorists needed to drive a vehicle other than their own in genuine emergency circumstances. Volunteering to move a vehicle, for example, where another motorist had been taken ill or been involved in an accident, could lead to the "assisting" driver being prosecuted for no insurance if the other car's insurance did not cover use by any driver. To alleviate this loophole, an extension to UK Car Insurances was introduced allowing a Policyholder to personally drive any other motor car not belonging to him/her and not hired to him/her under a hire purchase or leasing agreement. This extension of cover, known as "Driving Other Cars" (where it is granted) usually applies to the Policyholder only. The cover provided is for Third Party Risks only and there is absolutely no cover for loss of, or damage to the vehicle being driven. This aspect of UK motor insurance is the only one that purports to cover the driving of a vehicle, not use.
You’ll notice that none of that liability coverage pays for your car or injuries, nor for any injuries your passengers sustain if you cause a wreck. This is why many people — particularly those whose car isn’t yet paid off — want “full coverage” car insurance. This isn’t actually a type of coverage, but instead typically refers to policies that include liability coverage, plus comprehensive and collision coverages.