Todays im going to learn Java ! Interface: An interface in Java is a blueprint of a class. It has static constants and abstract methods. The interface in Java is a mechanism to achieve abstraction . There can be only abstract methods in the Java interface, not method body. It is used to achieve abstraction and multiple inheritance in Java . In other words, you can say that interfaces can have abstract methods and variables. It cannot have a method body. There are mainly three reasons to use interface. They are given below. It is used to achieve abstraction. By interface, we can support the functionality of multiple inheritance. It can be used to achieve loose coupling. Collections in Java https://www.javatpoint.com/collections-in-java Java Collections can achieve all the operations that you perform on a data such as searching, sorting, insertion, manipulation, and deletion. Java Collection means a single unit of objects. Java Collection framework pro...