تعريف ومعنى "the half of it"

What is the origin of the idiom "the half of it" and when to use it?

The idiom "the half of it" originated from the notion that a given situation or story has more to it than what has been revealed or explained. It is mainly used to suggest that the information or details provided are only a fraction of the whole, and there is much more that remains untold or unshared.