Java is an object-oriented programming language that sources its syntax from C++, and C. Core Java is used mostly to generate and develop portable codes for the development of Java applications for desktops and even servers.
Any software developed using Java can work perfectly on any platform, and that is why it is often referred to as platform-independent programming language. Core Java, on the other hand, does not support this as it can only be used to develop Java applications for servers and desktops.
While Java is purely a programming language, Core Java is mostly referred to as a computing platform, which makes it easy for any software developed to be used. If you want to learn more about other editions of Java, Core Java is an important version of Java that you should learn. And beginners who want to learn more about all the basics of Java should also learn more about Java.