Anyone who drives a car needs motor insurance, of course – the law requires it. Yet even though this makes it probably the most widely purchased kind of insurance, there is an almost overwhelming choice. The availability of online motor insurance both increases the range of products available, but also helps to make sensible choices between them considerably easier.

When shopping for anything – whether online or on the high street – you need first to make a few decisions about just what it is you want. When it comes to motor insurance, the first question is whether you are after third party only, third party, fire and theft, or comprehensive insurance cover. Whatever your choice, however, purchasing the insurance online can realise valuable discounts on the premiums you will need to pay.

Third party only motor insurance is the minimum level of cover required by law. This ensures that the insured person is covered for liability for injuries to anyone else (including passengers in the policy holder's vehicle); any damage caused to someone else's property; loss or damage to third parties caused by passengers in the policy holder's vehicle; and loss or damage suffered by third parties caused by a trailer or caravan attached to the policy holder's car. This most basic level of cover is likely to attract those with a very low-value vehicle, where the cost of almost any kind of repair is likely to outweigh the value of the car itself.

Just as the title suggests, third party fire and theft motor insurance covers a somewhat wider range of risks, including the possibility of fire or theft of the vehicle. Although this will provide cover against all claims from third parties, it does not cover accidental damage caused as a result of the policy holder's own fault. Therefore, this level of cover is very popular for drivers of relatively low-value cars which are nevertheless worth more than the claims excess that applies to the insurance cover. Third party, fire and theft insurance is also attractive to younger drivers, for whom fully comprehensive insurance is likely to be prohibitively expensive, for drivers who use their cars quite rarely or for drivers who have yet to accumulate a significant no-claims discount.

Finally, of course, for regular drivers of cars of any value there is fully comprehensive insurance. Although comprehensive motor insurance is the fullest type of cover available, it nevertheless varies from insurer to insurer. Here once again the internet is an invaluable tool for comparing just what is included in any particular insurer's version of the comprehensive option. All can be expected to cover not only the third party, fire and theft benefits mentioned above but also accidental damage to the policy holder's own vehicle, personal injury benefits; benefits to cover the cost of medical treatment; and damage to or the loss of personal possessions in the vehicle.

But there might also be other benefits packaged with the comprehensive option, such as a courtesy car if your own breaks down, is stolen or is involved in an accident; protection of any no-claims discounts; cover for driving abroad in Europe; and legal expenses for the pursuit of claims if you are involved in an accident which was not your fault.