abdominal paracentesis insertion of a trocar through a small incision and into the peritoneal cavity to remove ascitic fluids or inject a therapeutic agent. This is most often done to remove excess fluid in a patient with cirrhosis of the liver. Called also abdominocentesis and peritoneocentesis.
Abstraction is the act of representing essential features without including the background details or explanations. In the computer science and software engineering domain, the abstraction principle is used to reduce complexity and allow efficient design and implementation of complex software systems.
An abstract class is a class that can not be instantiated but that can contain code. An interface only contains method definitions but does not contain any code. With an interface, you need to implement all the methods defined in the interface. If you have logic that will be the same for all the derived classes, it is best to go for a abstract class in stead of an interface. You can implement multiple interfaces but only inherit from one class.