Daytime running lights not done on all cars. Their purpose - good visibility of the car to other drivers and pedestrians. DXO mark the car in front, behind them is not. Daytime running lights for the convenience of the motorist are included along with the plant engine, it is rarely necessary to do this on purpose. Accordingly DRL work on the car during its movement.
If your car is not DRL, it is to indicate while driving on any roads at any time of the day you need dipped headlights.

Be sure to include this light in the tunnel, even if it is day or in the tunnel there is light. This rule is imposed in case of sudden switch-off of lighting. If the vehicle is in such a situation will not be included dipped headlights, this can lead to accidents. An accident waiting to happen maybe for those seconds that it will take the driver to the driving lights, while his car will move in absolute darkness.

If it is raining, snowing or foggy, that is, the appearance is far from ideal, you also need dipped headlights.
When you drive at night outside a city or village, you need high beams. The light is used rarely: the streets are lighted and many other traffic participants, which can dazzle high beams.

You should always switch the high beam to the middle if you are going to meet a car. The distance should not be less than 150 metres. Even if the oncoming car appear further 150 meters away from you, and the driver shows you his blind (quick switches between far and near light), you must turn off the high beams.
Is it worth to switch from upper to lower beam when approaching the crest of pajama to avoid blinding oncoming and passing cars. In these circumstances, the pre-driver will not see them, as the survey closes slide.

The SDA is not specified at what distance to a passing car you must turn off high beam headlights. But it says that you must not dazzle other drivers. So if you caught up with the car ahead, turn off the high beams.
Not every vehicle has fog lights. Sometimes the drivers themselves equip them to your car, the rules do not prohibit it. The immediate purpose of these lights is to illuminate the road when there is rain or fog covers. If you don't see very well the road ahead, you should turn the fog lamps together with near or far light of headlights.

There are fog lights that illuminate your car back. Such lamps are in any case can not be connected to the stop signals, so as to include them only in fog, rain or snow. With good visibility of the road the inclusion of this lighting your car on the road is excessive.

If you are traveling in a snowstorm or downpour, the best option in this situation is to turn on the fog lights plus low beam. High beams will blind yourself: the light will be reflected from snow or rain, and return you in the eye.

Allowed to turn only fog in order to identify your car while driving. But maybe it's just a day when it's not raining, and in any case not in the tunnel.
If you decide to stay on the road at night, the rules require you to turn on your car lights. The way these lights are not lights, but they will allow other drivers to notice your car in advance. When standing on the side of the car is not marked with Parking lights, it can easily lead to a serious accident.