Pressure

pressure is defined as the force acting normally per unit area. If F is the force acting normally on the area A, then

Pressure = Force/ Area

In SI system(F) and area (A) are measures in newton(N) and square meter (m²) respectivly. So, Nm^-2  is the unit of pressure SI system. 1 Nm^-2 is also called Pascal(Pa), ie  1Nm^-2= 1Pa. though the force associated with the pressure at a point is a vector quantity, the pressure itself is a scalar ie the pressure has no direction.