The space around a body within which its gravitational force of attraction is experienced, is called its gravitational field.
Gravitational field strength or gravitational field intensity
The gravitational field intensity at a point is defined as the force experienced by a unit mass placed at that point.
Intensity of the field experienced by a test mass
Let M be the mass of a body around which a gravitational field exists. Let m be a test mass placed in this field. The test mass is so chosen
that it does not influence the gravitational field. The arrow over
indicates it is a vector quantity, whereas mass is a scalar quantity.
A force field is the force experienced by the unit mass m. The intensity
of the field is the force experienced by the unit mass.
If the test mass m were free to move, it would move with an
acceleration towards M.
The gravitational field intensity is defined as the free acceleration experienced by a test mass at that point.
indicates it is a vector quantity, whereas mass is a scalar quantity.
field is the force experienced by the unit mass m. The intensity 
The gravitational field intensity is defined as the free acceleration experienced by a test mass at that point. 
C.G.S. system are dyne gm-1 or cms-2 
SI system are Nkg-1 or ms-2 
