DisclaimerThis post is a personal study note created while learning the topic discussed. Some information may be inaccurate or incomplete. If you notice any errors or have suggestions, I’d sincerely appreciate your feedback.
I’ll start by getting a quick overview of what Java is, then go through how to install it and run a simple program. I’ll also try making a small program to get a feel for how Java programming works. The goal of this chapter is to give myself a rough idea of the overall process, and starting from the next chapter, I’ll go through the Java basics step by step.
Then let’s take a look what java is!
Java, first introduced in 1995, is one of the most widely used programming languages in the world. Its core philosophy is “Write Once, Run Anywhere”, which means that a program written in Java can run on different operating systems without modification. This is possible because Java runs on the JVM (Java Virtual Machine), a middle layer that allows the same program to be executed across Windows, macOS, Linux, and many other environments.
Java follows the principles of object-oriented programming (OOP), which structures a program into multiple objects that interact with each other. This approach increases code reusability, makes maintenance easier, and is especially effective for large-scale projects and team collaboration. Over decades of development, Java has accumulated a wide range of libraries and frameworks, such as Spring for web development, Hibernate for database integration, and the Android SDK for mobile app development.
Because of its stability and security, Java is widely used in large-scale systems such as those run by banks, insurance companies, and government agencies. However, Java is not the only choice for large-scale applications. The choice of language depends on the service’s needs. For example, Instagram was originally built using Python with the Django framework, and many modern large-scale services also make use of Go, JavaScript (Node.js), C++, and other languages alongside Java.
For beginners, Java may feel a bit strict due to its detailed syntax rules, but this very structure helps build a solid foundation in programming. Therefore, Java is not only a beginner-friendly language but also a powerful and practical tool used in real-world development. Together with other programming languages, it continues to play a vital role in shaping the modern software ecosystem.