The nature of work done can be categorized in three classes. They are positive work, negative work and zero work. The nature of work depends on the angle between force and displacement.
Positive work- if the applied force displaces the object in its direction, then the work done is known as positive work.
Negative work- if the force and displacement work in the opposite direction, then the work done is known as negative work.
Zero work- If the force and displacement act in perpendicular to each other, then the work done is known as zero work.