Work is a scalar quantity because it is the dot product of two vectors (Force and displacement). Dot product of two vectors becomes scalar quantity. So, work done has only magnitude but not direction. Work done may be positive, negative or zero.

Which quantity is work done?

Work has only a magnitude but no direction. The formula for work is written as a dot product of force and displacement. Therefore, work is a scalar quantity.

What is work is it scalar or vector quantity?

Work is dot product of vectors force and displacement , and dot products are scalar. Therefore work is an scalar quantity.