While specific insurance laws can vary, generally, if you have given someone permission to drive your car, they will be covered under your insurance policy. So in this way, yes — anyone who drives your car will automatically be covered by most insurance policies.
Insurance companies generally ask that everyone in the household who possesses a driver’s license be listed on the insurance policy. In this way, you can be certain that anyone of legal driving age and possessing a license in your household will in effect be insured and covered by your policy.
There are some cases where someone you know might not be covered by your insurance policy; for example, if your girlfriend or a relative comes to visit you or moves in with you and uses your car without permission, then gets into a car accident, that person would likely not be covered.
Permission seems to be the key here. If you authorize someone to use your car, it doesn’t matter if their name is listed on the insurance policy or not. This applies to Burtonsville and Adelphi residents, and everyone in between. Whether the person lives in your household or elsewhere, as long as you’ve granted them permission, they will be covered by your insurance policy. That said, there may be some exceptions. Be sure to check with your insurance company to verify how your specific policy works.