What is the difference between coordination entity and coordination sphere?

CBSE Class 12
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What is the difference between coordination entity and coordination sphere ?

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Coordination entity:
A coordination entity constitutes a central metal atom or ion bonded to a fixed number of ions or molecules.
Example: In K4[Fe(CN)6], [Fe(CN)6] 4- represents a coordination entity.

Coordination sphere:
The central atom/ion and the ligands attached to it are enclosed in a square bracket and is collectively termed the coordination sphere.
Example: In the complex K4[Fe(CN)6], [Fe(CN)6] 4- is the coordination sphere.
If enclose the coordination entity in square bracket, and indicate the net charge on the coordination entity, then it is known as coordination sphere. For example, [Fe(CN)6]4-, is the coordination sphere, with Fe(CN)6, as coordination entity.