As the others say, however be VERY careful about understanding the situation regarding insurance, there are many pitfalls even if you think you are covered.
I'm not suggesting this is the case for you, but just as an example it might state on your insurance that no-one under 25 is covered, but a 24yr old son/daughter with their own car insurance might think they are OK to drive your car using their cover, but your insurance would not be valid with that driver so their insurance would not be valid because the other car must have valid insurance. Get my drift?
Just be careful. Driving someone else's non-MOT'd/taxed car might possibly be a tricky case, for example if their insurance was valid for them to drive under those circumstances but it was not valid if someone else was driving, hence your insurance would not be valid either.
I might be over cautious, but driving without insurance is a big no-no.