One condition of holding a driving licence is that you must inform the Driver and Vehicle Licensing Agency (DVLA), or the Driver and Vehicle Agency (DVA) in Northern Ireland, if your health deteriorates in any way that affects your ability to drive. This also applies if your eyesight deteriorates to the point that you can no longer meet the driver's eyesight requirements.

Potential driving instructors (PDIs) will have their eyesight tested at the start of their Part 2 examination. A number plate, where the letters and figures are 79 mm tall and 50 mm wide, must be read at a minimum distance of 26.5 metres (87 feet). If a PDI can't pass this test, their Part 2 examination will go no further. This won't, however, affect their licence to drive, as the ADI eyesight test standard exceeds the legal eyesight requirement.

A candidate should tell DVSA of any special needs or circumstances when they book their driving test. No matter how serious the disability might be, the candidate will still take the same driving test as any other person. However, more time is allowed for the examiner to discuss the candidate's needs and talk about any adaptations fitted to the vehicle.

Cars, light goods vehicles, invalid carriages and motorcycles can be parked at night without lights on roads with a speed limit of 30 mph or less. They must comply with any parking restrictions and face the direction of the traffic flow.

Always switch off the engine, remove the key and lock your car, even if you're only leaving it for a few minutes.

When leaving your car, take all valuables with you, if you can. Otherwise, lock them out of sight.

When driving a motor car, a learner driver who holds a provisional driving licence must
- display red L plates (or D plates in Wales) to the front and rear of the vehicle
- be insured to drive the vehicle
- be accompanied by someone who's at least 21 years old and who has held for at least three years (and still holds) a full licence for the category of vehicle being driven.

Approved driving instructors and trainee driving instructors are issued with an identification certificate. This must be displayed on the windscreen of a vehicle that's being used for a driving lesson.

The details on your motor insurance certificate show who, when and what's insured. You'll have to produce the certificate if you've been involved in an incident and when requested by the police.

Drivers must be able to read a modern vehicle number plate from a distance of 20 metres. If you need glasses to do this, then you must wear them at all times when you're driving.

Fog lights will help others see you, but they must only be used if visibility is seriously reduced. You must turn fog lights off when visibility improves, to avoid dazzling other road users.

Driving a vehicle without insurance cover is illegal. If you cause injury to anyone or damage their property, it could be very expensive and you could also be subject to criminal prosecution.

A successful candidate with vision in only one eye will be given an unrestricted pass certificate. As with all drivers, the licensing authority (DVLA) must be notified of any medical conditions when applying for a licence, and when those conditions develop or change.

Double white lines along the centre of the road are usually found in places where there's a poor view ahead, usually caused by bends in the road. When the line nearest to you is solid, you may cross it to pass a stationary vehicle, providing that it's safe to do so.

Photocard licences are valid for a maximum of 10 years. This is to allow the photographic likeness to be updated when the licence is renewed. However, the licence entitlement usually lasts until age 70.

The Driver and Vehicle Standards Agency will need to know that your pupil is profoundly deaf to make the appropriate booking arrangements. This should be recorded when booking the test. Approved driving instructors should be able to help any pupil with their application for a theory test or a practical driving test.

Don't park within 10 metres (32 feet) of a junction (unless in an authorised parking place). This is to allow drivers emerging from, or turning into, the junction a clear view of the road they're joining. It also allows them to see hazards such as pedestrians or cyclists at the junction.

Sometimes an insurance company will issue a temporary insurance certificate called a cover note. It gives you the same insurance cover as your certificate, but lasts for a limited period, usually one month.

Red rear reflectors show up when headlights shine on them. These are useful when you're parked at night but will only reflect if you park in the same direction as the traffic flow. Normally you should park on the left, but if you're in a one-way street you may also park on the right-hand side.

A 60 mph speed limit applies to a vehicle towing a trailer on a motorway; such a vehicle is also not allowed in the right-hand lane of a motorway that has more than two lanes.