Why CORE JAVA
Java is a general-purpose, class-based, object-oriented computer programming language that was designed by James Gosling at Sun Microsystems in 1995.
Platform Independent: This allows programmers to develop applications that can run on any operating system. Java is most widely used programming language. It is present everywhere. It really doesn't matter which domain you are working in, you will surely come across Java sooner or later!
Open Source: The good news is that Java is available for free! All the development tools and the environment (JRE & JDK) that is used to develop Java applications are absolutely free of cost.
Irrespective of the fact that you are tech savvy or not, most of us are badly bitten by the Android bug! Android is in great demand today and fortunately you need Java for Android development. Hence, the importance of Java has increased even more.
In spite of having a tough competition on the server side from Microsoft and other companies, Java is doing extremely well on mobile platforms.