Difference between Java and Core Java

Java

Java is a general-purpose programming language with a number of features that make the program well suited for use on the world wide web. Java Programming language enables programmers to write computer instructions using English commands rather than writing numeric codes. Like any other languages, Java has a certain set of rules that is used to determine how the instructions are written. Java can be used to create complete applications that can be run on a single computer. Java is an object-oriented programming model. As of 2016 Java is one of the most widely used languages in use, particularly for a client-server web application.

Core java

While Core Java is used for developing a general Java application, and core Java are having the concept of Java, it is fundamental for Java that will be used in any Java technology without this no one can learn advanced Java. Core Java literary means Stand alone and moreover Core Java packages are always started with Java.
Java is the basic level in which you will learn to write Hello and create basic Java program for calculators etc,  while in Core Java students will gain the expertise in Java collection, OOPS Concept, Polymorphism, Java Exception Handling etc.