what is the difference between extend and extends?

Answer 1

The keyword "extends" is used when a class inherits properties from another class.

class Cat extends Animal{
//
}

"extend" is not a Java keyword, as far as I know.

Answer 2

Extend is an invalid word in Java, no way extend is found in a Java code

Answer 3

Extend does not belong to Java.
Extends represents the inheritation keyword. When a class inherits attributes and methods from another class, you write:

class AClass extends AnotherClass

We also call "AClass" subclass, and "AnotherClass" super class, as the subclass always inherits properties from a super class