In this video the author talks about the basic concepts in propositional logic, explaining how important this concept is to understanding the basic concept of logic. He says that propositional logic is also called "sentential logic" or "statement logic". He states that a proposition is synonymous to claim, statement or insertion. He states that propositional logic deals with logical relationships between propositions taken as wholes. He states that in proposition logic the proposition is dealt as a whole and can be either completely true or completely false. He goes on and explains about compound claims and about basic compounding words like "and" and "or". This video is a good introduction to the understanding of the propositional logic.