What are the two "family parameters" of Revit?

What is the difference between "family category" and "Family type"? Why do family categories set family parameters? Why do the "family type" set parameters?

When you set the family category and family parameters, there is a family parameter .
When setting "parameter" of "family type", there are 4 definitions: " family parameter ", "Shared parameter", "type parameter", "Instance parameter".

In this way, there are two different " family parameters " that are completely identical in meaning. It's really confusing me to death!

Preliminary smoothing, as follows:

What is the difference between a 1 family category and a family type?
Family Category: A group of elements which classifies the building model based on the properties of the building components. such as doors, windows, columns, furniture, lighting equipment.
Family types: Families can have multiple types. Types represent different parameters (property values) of the same family.

What is the meaning of the 22 "Family parameters"? What is the difference between the "family parameter" and "Family type" parameters of the family category?

The "parameter" of " family type" is divided into "two types": " family parameter ", "Shared parameter", "" "two different parameter data": type parameter, instance parameter. 】

The family parameter of the family category is the placement behavior and the component properties of the various artifacts. The use of these components is related to the field of use, namely: the Division of labor related to the various professions (different division of labor uses the same thing).
" parameter " of "family type" refers to specific, subtle parameters, such as dimensions.

The "Family parameter " of "Family category" is the creation of my clan from the general direction, these parameters are all designed, just need to choose.
The " parameter " of the "family type" is a trivial matter and needs to be set by the software user.

What are the two "family parameters" of Revit?