The Abhidhamma is all about ‘seeing’ the aggregates (khandhas) 6 sense doors (ayatanas) and dhatus (elements) as not self.
Here are the first 3 chapter headings of the Vibhanga (translated as Book of Analysis).
Analysis of :
1. Aggregates
2. Bases
3. Elements
In the Introduction to the Vibhanga (Pali text society)
Iggelden writes
It is all very well to say ‘I know what needs to be done to break
the continuity of rebirth and death’. In fact very few people know of
even the most elementary reasons for the continuity of process, let
alone of breaking it. It is the detailed description, analysis and
reasons given for this cyclic process that the scriptures spend so
much care in putting before us.
It is all very well to say ‘What do I want to know all these
definitions of terms for, it only clutters the mind?’The question is,
though, how many people when they seriously ask themselves as to the
extent and range of some such apparently simple terms as greed,
hatred and ignorance, can know their full and proper implications and
manifestations within their own thoughts and actions…This the
scriptures are at pains to make clear to even the dullest
reader…”
He goes on in a similar vein for pages.
I hope you will study it Venerable. Abhidhamma is much more than theory if we grasp that it applies to each moment of life. It is a description of reality by the Blessed One.
So vipassana and Abhidhamma are not different as vipassana confirms directly what has been said in the Abhidhamma.