Light intensity refers to the amount of light that is emitted from a source or received by a surface. It is often measured in units called lumens or candelas. Higher light intensity means that more light is present, which can make an area brighter and more visible. Factors affecting light intensity include the distance from the light source and any obstacles that may block or absorb the light. For example, a light bulb will illuminate a room more brightly when it is closer to the floor than when it is farther away.