As the name suggests, it is clear that the lightings that are used to lighten up the outdoor of homes, which means spaces like a garden, a balcony, a street, a wall, etc. are known as Outdoor Lighting. These lights are generally useful and put out to create night-time aesthetics, safety reasons, recreation, night vision, and accessibility.
The characteristics of outdoor lightings are that they should be bright, effective, energy-efficient, weather-proof, and should have a long life.

Image result for home outdoor lighting

The brightness of these lights has become one of the major criterions since their purpose is to offer a vision in the night time when there is no support of the daylight. So the brighter they are, the better it is for visibility.
The requirement of brightness varies with various kinds of lightings. If the incandescent bulbs are used, 65-70 watt is preferred. If not, then 20 watt CFL or 10-15 watts of LED lights is enough for exterior lighting.

Also, another question that arises is, how long should these outdoor lightings be kept active. These lights have no use in the daylight since the natural light of the sun is enough to provide a well-lit space and vision. In the evening after the dusk, these lights can be put to use.

Usually, people prefer to keep these light active from dusk to dawn. But there is also a part of the population that believes to turn the lights down or shut them when they go to bed.

Both of these situations have positives and negatives. Keeping the lights on may alert the burglars about the owner’s presence but on the other hand, may shoot up the electricity used and thus the bill.
Turning it off at night may attract some kinds of mishaps or low visibility but does save energy and is an environmental-friendly option.
So it completely depends on individual to individual to decide about the activeness of these outdoor lightings.