Along the road
If there is a traffic island with a 'Keep left' sign in the middle of the road you pass to the left of the island. You must not drive to the right.
A single broken line in the middle of the road, with short markings and long gaps, is a 'Centre' line. You should normally drive to the left of this line except when overtaking.
A single broken line, in the middle of the road, with long markings and short gaps, is a 'Hazard warning' line. Do not cross it unless you can see the road ahead is clear.
Keep between the 'Traffic lane' lines -- the short broken white lines which divide the road into lanes. Keep in the left-hand lane unless you are overtaking, turning right or passing parked vehicles.
The 'Hazard warning' line may replace the normal lane line near a hazard.
Do not change lanes unless it is safe to do so.
Do not move unnecessarily from lane to lane. If you need to move into another lane, first look to see that it is safe to do so, remembering to use the mirror. If it is safe to move over, signal before doing so. Make sure this will not force another driver to swerve or slow down.
In a traffic hold-up or in slow moving traffic, do not try to jump the queue by cutting into another lane or by overtaking the vehicles waiting in front of you.
Hazard warning area -- an area of roadway hatched with white lines. It is there to separate traffic streams liable to be a danger to one another or to protect traffic turning right. Do not drive over or enter the area.
Along the edge of the road
Edge lines -- on some roads solid or broken white lines are marked on the edge of the roadway.
Hazard markers -- these small discs or rectangles are found on roadside objects or special posts where there is a hazard. Red markers are used on the left-hand side of the road, white markers on the right-hand side of a single two-way carriageway and amber markers on the right-hand side of a dual carriageway adjacent to the central divider.
Reflecting road studs
Road studs delineate the edges of a carriageway or the division of traffic lanes. These help drivers at night or in poor visibility.
White studs mark the lane lines and the centre of the road. Red studs mark the left edge of a carriageway. Amber studs mark the right edge of a carriageway adjacent to a central divider. Green studs indicate the edge of any part of the carriageway at a road junction, layby or passing place.