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Colloidal solution.

A true solution is like sugar or salt solution.  It is totally homogeneous. 

A suspension is like a sand or chalk power or atta mixture or solution in water. It is heterogeneous.  The particles are very big and are suspended in water. But after some time they settle down at the bottom.

A colloidal solution is also a heterogeneous solution but the particles suspended are very small and the solution could look like homogeneous solution.  But many particles of soap together are visible in the form of bubbles.  The particles suspended are less than the sizes of a suspension.

The solution of soap  in water is known as colloidal solution.