Introduction to Java

Welcome to our Java programming course. We will start this course with introduction to the Java and try to cover some of the aspects of Java programming language like

  1. Why Java?
  2. Features of Java language which make it unique.
  3. Some Application which are good candidate for Java.

1. Introduction to Java

Java is a general-purpose programming language that is object-oriented and class-based. It is one of the most popular programming languages in the world, and is used to develop a wide variety of applications, including web applications, mobile applications, desktop applications, and embedded systems. Some of the feature which makes this language so popular

Introduction to Java
  • Object-oriented programming: Java is an object-oriented programming language, which means that it uses objects to represent data and behavior. This makes Java programs easy to understand and maintain.
  • Compiled language: Java is a compiled language, which means that it is converted into machine code before it is executed. This makes Java programs very efficient, and they can run on a wide variety of platforms.
  • Class-based: Java is a class-based language, which means that it uses classes to define the structure of objects. This makes Java programs well-organized and easy to extend.
  • Portable language: Java is a portable language, which means that Java programs can be run on any platform that has a Java Virtual Machine (JVM).
  • Secure language: Java is a secure language, which means that it is designed to be resistant to security vulnerabilities. This makes Java programs safe to use in a variety of environments.
  • Robust: Java is a robust language.

2. Terminology

While we will cover each and every concept in great details, it’s important to cover few Java terminology as part of the introduction to Java.

We start our journey by writing the source code in Java. Once the code is ready, it’s compiled by the Java compiler to convert it to byte code which is also known as platform independent code. The byte code is eventually run by the JVM.

What do you think the benefits of compiling and converting the Java code to byte code before running it on JVM? One we know as platform independent code what other benefits can you think of?

3. Application of Java

There are number of application where Java is a default choice. Lets take a look at few use cases:

  • Web applications: Java is a popular language for developing web applications. This is because Java is portable, secure, and has a large library of APIs for developing web applications.
  • Mobile applications: Java is also a popular language for developing mobile applications. This is because Java is supported by a wide variety of mobile platforms, including Android and iOS.
  • Embedded systems: Java is also used to develop embedded systems. This is because Java is portable and secure, and it can be used to develop applications that run on a variety of devices.

4. JDK, JRE and JVM

JVM, JRE, and JDK are part of the java ecosystem to develop and run your Java application. Each component provide a specific work and play a critical role while running your Java application. We will take a detailed look on all these components in our next lesson


In our introduction to Java, we take a look at some of the core feature of Java programming language. Java is a powerful and versatile programming language that is used to develop a wide variety of applications. The source code for this course is available on our GitHub repository. You can also use our online free Java compiler to run these programs.