Low beam, also known only as low beam, should be used when visibility is impaired by increasing darkness or adverse weather conditions such as rain, fog or snow. They are very different from high beams.
High beams are the brightest lights in the front of the car and should only be used when your visibility is impaired and when there are no other vehicles in front of you or approaching. However, the high beams should not be used in dense fog or heavy snow, because the light is simply reflected off the driver, reducing your ability to see ahead instead of increasing it. In this case the fog lights should be used.
Some, but not all, cars have two front fog lights, designed to emit a wide beam of light that illuminates the edges of the road closest to the front of the car. This makes it easier to see the sidewalk in thick fog. In modern cars, they are sometimes used to mimic the effect of directional (or swivel) headlights, so when you turn the steering wheel, the fog light for that side of the car will illuminate to illuminate the road in the direction you are turning.
Then there are the direction indicators: in the front part of the vehicle there will be two orange direction indicators (also called flashers), one on each side; these flash to let other vehicles know that you intend to make a turn.