The free throw lane is the space on a basketball court from the baseline to the free throw line. It is 12ft wide and 19ft long. The free throw lines help form the elbows, while the restricted arc and the block are also part of the free throw lane.
The free throw lane also contains lines on the side. These are used to align players during free throws in preparation for the rebound. A player who steps into the free throw lane during free throws has committed a lane violation. You can read more about lane violations in Basketball Lane Violation.