What is the use of notation in Machine Learning?

Answer 1

What kind of notation do you mean?
We need a mathematical notation for specifying the formulae we want to use. Or do you mean any particular notation standard?

Answer 2

I mean the Mathematical formula

Answer 3

A formula is just an abstract and standardized way of expressing how the "machine" should proceed in the "learning process".
How should the machine "know" how to "learn" if we don't give it a minimum set of algorithms and conventions? And that's why we need math and write forumla.

We can think of machine learning as as kind of applied mathematics... (at leat partly)