The video tutorial explains the concept of the consumer interface in Java, highlighting its role in the 'forEach' method. It discusses how a consumer is a functional interface with an 'accept' method that processes elements without returning a value. The tutorial demonstrates creating a consumer implementation for integers, emphasizing the use of lambdas and custom implementations. It concludes with a brief mention of mapping, to be covered in the next session.

What new insight or understanding did you gain from this video?