For you to be properly insured, you have to be honest when you're describing which class or type of use you need, when you're getting your car insurance quote.
Social, Domestic and Pleasure usually has the cheapest premiums, which increase as you go further up the scale to Commercial. But if you're really using your car for a purpose that's classed as Commercial, don't be tempted to try and get away with Social, Domestic and Pleasure - in the eyes of the law it will be uninsured, and there are severe penalties for driving without insurance (as we describe in Why you need car insurance).
Social, Domestic and Pleasure
This covers the drivers named on the policy for normal day to day driving - shopping, visiting friends or family and pleasure driving such as going to the park or on holiday. However, it doesn't include commuting to work.
Commuting is the next class up, and covers everything included in Social, Domestic and Pleasure, plus driving to and from a permanent place of work. Driving your car to the train station and leaving it there while you go to work counts as commuting. So does giving someone a lift to their place of work; it's best to check when you get your quote.
Business use - class 1
If you're using your car as part of your job, to drive to other sites as well as your usual place of work, this counts as Business use - class 1. It doesn't include commercial use (such as deliveries) or door-to-door selling.
Usually your spouse will also be covered for Business use - class 1, but no other named driver. Best to check when you get your quote.
Business use - class 2
This is much the same as class 1, but it generally covers you (the policyholder) and a named driver, in connection with your business. However, different underwriters have their own rules about what it covers, so again, check when you get a quote.
Business use - class 3
This is the one you need if you are racking up the miles - like salesmen who may also be carrying samples.
Anything else is likely to need Commercial insurance. That includes using your car as a taxi or minicab or driving a limo, or using your car to give paid driving lessons.
Of course, if you're driving a van and using it for business, you need Admiral Van Insurance. Job done!