A compulsory car insurance scheme was first introduced in the United Kingdom with the Road Traffic Act 1930. This ensured that all vehicle owners and drivers had to be insured for their liability for injury or death to third parties whilst their vehicle was being used on a public road. Germany enacted similar legislation in 1939 called the "Act on the Implementation of Compulsory Insurance for Motor Vehicle Owners."
Comprehensive insurance covers all of the above and damage to the vehicle caused by the driver themselves, as well as vandalism and other risks. This is usually the most expensive type of insurance. It is custom in the UK for insurance customers to refer to their Comprehensive Insurance as "Fully Comprehensive" or popularly, "Fully Comp". This is a tautology as the word 'Comprehensive' means full.
Road Traffic Act Only Insurance differs from Third Party Only Insurance (detailed below) and is not often sold, unless to underpin, for example, a corporate body wishing to self-insure above the requirements of the Act. It provides the very minimum cover to satisfy the requirements of the Act. Road Traffic Act Only Insurance has a limit of £1,000,000 for damage to third party property, while third party only insurance typically has a greater limit for third party property damage.
But liability coverage levels come in threes — you’ll probably see something like 50/100/50 up to 250/500/250 in typical policies. You can think of these limits like: individual injuries / total injuries / property damage. Insurers are a little more technical, calling them bodily injury liability, total bodily injury liability and physical damage liability.