You may now have a car and decide to take an insurance. Or you are working in UK and you are a non resident, with a car and in need of car insurance. But even if you are a non UK resident, that does not mean you have to have problems with the car insurance. You can easily get it.
Some insurance companies even offer some small rebates for non UK citizens. Some other companies chose to give you car insurance but as long as you are the one driving the car, in whatever country you are. But if you are traveling from one country to another it is best to verify the policy with the insurance company, before going abroad. There are many companies in UK that do not allow non UK people to get insurance unless they stay in UK for a few months or sometimes for more than 1 year. In this case renting a car is the best choice because it comes with insurance.
But there is another easier way: get an international driver’s license. If you have this, then you will get license so much easier. Do this especially if you are an American citizen because your US driver’s license is not accepted. And even so, there are ways to avoid all the hassle with the insurance in UK.
Also, if you have an insurance in your own country, and the country is part of EU, then you may not have to change the insurance you have. But this depends on the country you are coming from and the treaties they have with UK. Also, if you are a student, you may require additional paperwork in order to get the car insurance. The laws in UK are pretty strict when it comes to regulating the car traffic and insurances.