The motto of Java is “write once, run anywhere.” And it’s true. You can find Java code just about anywhere. It is used in Android app development, web development, game development, smart devices, and so much more.

In this article, we will take a look at Java’s interesting history. Then, we’ll explore all the places Java code is used.

What makes Java interesting?

Java was developed by a group of developers at Sun Microsystems in 1995 and is now owned by Oracle. The goal of the developers who designed Java was to create a language that could run on appliances. They were already thinking ahead to the time we live in now, where houses are full of smart devices and smart appliances. This was one of Java’s selling points — that you could write your code once in the language and run that code anywhere. Not just on every operating system but every type of hardware.

However, it would be quite a few decades before smart devices became a way of life. Despite this, Java still became popular and for a completely different reason. Java was released about the same time the Internet was born. Java had a feature called applets that could run inside a web browser. A lot of web applications were built in Java when most websites still consisted of static pages.

Java gave web developers the ability to build dynamic websites that reacted to user input, and its popularity took off from there.

Java was also based on the C and C++ programming languages, which were very popular. C++ was usually the programming language taught in computer science courses in those days, so many programmers were familiar with it, even today. They could apply that knowledge of C++ to programming in Java.

What is Java used for?

Java can be used in many different applications, but here are the most popular ways the language is used:

Android mobile apps

Java is the official language for Android mobile app development. In fact, the Android operating system itself is written in Java. Even though Kotlin has recently become an alternative to using Java for Android development, Kotlin still uses the Java Virtual Machine and can interact with Java code. Today, Android has 85% of the global market share for mobile devices. Therefore, developing Android apps is probably the most popular use of Java just because of the prevalence of Android phones.

Desktop applications

Java has been used to create desktop applications since its inception. AWT, Swing, and JavaFX are Java libraries that give desktop application developers pre-built components like buttons, menus, and form fields that they can use to build full-featured desktop applications.

Web applications

Java first became popular as a web development language because it provides applets that can run in a web browser. Applets are a thing of the past, but Java is still very popular for creating back-end web applications, which run on a web server. Now web developers use Java technologies like Struts, Servlets, or JSP instead of Applets to create all types of full-featured web applications.

Game development

Java is a free, open-source language. Many game developers use it because they can get started without paying any licensing fees and because of the powerful Java 3D game engine, JMonkeyEngine. Some video games written in Java include Tetris, The Sims 3, Space Invaders, Street Fighter II, and Contra. One of the best-known Java games, Minecraft, was created by a single developer.

Big data processing

Java and big data go hand in hand. Many of the top applications used for big data are written in Java. Hadoop is a Java framework that helps data scientists process large datasets. Spark is a tool that data scientists use for stream processing, machine learning analytics, and other big data processes. Storm handles real-time data streams. All of these frameworks are written in the Java programming language.

IoT applications

Java was originally designed to run on all types of hardware, making it one of the main programming languages used for the Internet of Things, or IoT. IoT refers to a network of physical devices that connect and exchange data over the Internet. The devices include smartwatches, wearables, smart TVs, smart lighting, and more.

Distributed applications

Many distributed applications run in a cloud environment and are designed to scale when the load changes. But distributed applications are not necessarily easy to deploy and manage. Java provides the Java Intelligent Networking Infrastructure or JINI to make distributing applications simpler. JINI is an infrastructure to provide, register, and manage distributed Java applications.

Cloud-based applications

Java is also heavily used in cloud-based applications. Because of its low cost and wide use, many companies use it to develop SaaS, IaaS, and PaaS services in the cloud.

Enterprise Development

Java is used heavily in enterprise development to build intranets and internal software for all types of businesses, big and small. Java Enterprise Edition (Java EE) is specifically designed for enterprise development. It comes with network applications, web services, and a scripting environment that make setting up an intranet with Java simpler.

Getting started with Java

Ready to get started with Java? To start learning, check out our Learn Java course, which will teach you basic programming concepts and introduce you to building complete applications with the Java programming language. To explore even more of what you can do with this popular language, you can learn how to build Android apps with Java or take more of our Java courses.

Java Courses & Tutorials | Codecademy
Java is one of the most popular programming languages out there. Released in 1995 and still widely used today, Java has many applications, including software development, mobile applications, and large systems development. Knowing Java opens a lot of possibilities for you as a developer.

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