How many laws of friction are conventionally used?

Question

I was studying laws of friction. Wikipedia says there are three laws based on Coulomb's model of friction.
However, most of the other websites say there are five laws, stating

When an object is moving, the friction is proportional and perpendicular to the normal force.

Friction is independent of the area of contact so long as there is an area of contact.

The coefficient of static friction is slightly greater than the coefficient of kinetic friction.

Within rather large limits, kinetic friction is independent of velocity.

Friction depends upon the nature of the surfaces in contact.

I am confused which to choose. I mostly prefer Wikipedia for making my notes, however this is creating confusion.
I want to know, which ones do we choose and use conventionally?
(I myself feel that the three laws are better as they seem technical and not redundant.)

Young Kindaichi · Accepted Answer

I would not see them as law, I would rather call them properties of friction forces based on experimental facts. All the properties (Laws) you have given are true ( at certain approximation) for frictional forces.
Friction depends on detailed structure
at the molecular level and is generally too complicated to be analyzed
from basic principles. Consequently, friction must be treated phenomenologically,
described by empirical rules. The magnitude of the
force of friction varies in a complicated way with the nature of the surfaces
and their relative velocity. In fact, the only thing we can always
say about friction is that it opposes the motion that would occur in its
absence.

How many laws of friction are conventionally used?

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