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Java (programming language)

technology Maturity 7-9

Java is a way to talk to computers.

Duke (Java mascot) waving.svg
Duke (Java mascot) waving.svg
It helps people make new things. You can use it on many machines. It can even work on big computers. It is very helpful for us. Do you like computers?
James Gosling 2008.jpg
James Gosling 2008.jpg

45 words

Java is a way to talk to computers.

Duke (Java mascot) waving.svg
Duke (Java mascot) waving.svg
It lets people write code once. Then, it can run on many machines. This works because of a special tool. It acts like a translator for the computer.
James Gosling 2008.jpg
James Gosling 2008.jpg
James Gosling helped make it. It was once named after an oak tree. Later, it got its name from coffee. Java is used on many things. It works on laptops and game consoles. It is a very popular tool for making software.

85 words

Java is a way to talk to computers.

Duke (Java mascot) waving.svg
Duke (Java mascot) waving.svg
It is a programming language. This is a set of rules for writing code. James Gosling helped create it in 1991.
James Gosling 2008.jpg
James Gosling 2008.jpg
He worked at a company called Sun Microsystems. At first, the project was named Oak. Later, it was named Java after a type of coffee.

Java has a special goal. It lets people "write once, run anywhere." This means code can run on many different machines. It does this using bytecode. Bytecode is a middle step for the code. A tool called a Java virtual machine, or JVM, reads this bytecode. The JVM acts like a translator. It turns the bytecode into a language the computer understands. This works on laptops and even supercomputers.

Java also helps keep computers safe. It has a tool called a garbage collector. This tool manages memory. Memory is the space a computer uses to work. The collector finds parts of memory that are not being used. Then, it clears them out automatically. This helps the programmer focus on their work.

182 words

Java is a very popular programming language used to talk to computers.

Duke (Java mascot) waving.svg
Duke (Java mascot) waving.svg
It is a high-level language, which means it is designed to be easy for people to read and write. One of its biggest goals is a rule called "write once, run anywhere." This means a person can write code on one computer and it will work on many others. Java is also memory-safe, which helps prevent many common computer errors. This makes it a very important tool for building all kinds of software.
JavaUniverse.png
JavaUniverse.png

To make this "run anywhere" goal work, Java uses a special middle step. Instead of turning code directly into computer language, it turns it into something called bytecode.

JavaUniverse.png
JavaUniverse.png
A tool called the Java virtual machine, or JVM, then reads this bytecode. You can think of the JVM as a translator that speaks the bytecode to any computer. This allows the same program to run on a laptop or a huge supercomputer. It also uses a garbage collector to manage memory automatically. This tool finds parts of the computer's memory that are no longer being used and clears them out.

The story of Java began in June 1991.

James Gosling 2008.jpg
James Gosling 2008.jpg
A man named James Gosling started the project at Sun Microsystems. He worked with Mike Sheridan and Patrick Naughton. At first, they called the language Oak after a tree outside an office. Later, they changed the name to Java after a type of coffee from Indonesia. The first public version, Java 1.0, was released in 1996. It quickly became famous because it could run inside web browsers.

Java has many different versions and editions for different jobs. For example, Java ME is made for devices with small resources. Java EE is used for large internet environments. There are also long-term support versions, which are called LTS versions. Some of these include Java 8, 11, 17, 21, and 25. These versions get special care and updates for a long time. The most recent version mentioned is Java 26.

James Gosling 2008.jpg
James Gosling 2008.jpg

You can find Java working in many places in your daily life. It runs on everything from small smart-cards to giant data centers. It is even used in game consoles and scientific supercomputers. Even though some newer languages are becoming popular, Java is still a major standard. It was once the third most popular language on GitHub. Because it is so widely used, it helps connect many different types of technology together.

413 words

Java is a high-level, general-purpose programming language. It is also known as an object-oriented language. This means it organizes software design around data, or objects, rather than functions and logic. Java is designed to be memory-safe. This helps prevent many common errors that can cause programs to crash. One of its most important features is its portability. Developers follow a principle called "write once, run anywhere," or WORA. This allows code to run on many different platforms without being rewritten.

JavaUniverse.png
JavaUniverse.png

To achieve this portability, Java uses a unique execution process. Instead of compiling code directly into machine code for a specific computer, it uses an intermediate step. The programmer's code is compiled into something called Java bytecode. Bytecode is a set of instructions that is not tied to any specific hardware. To run this bytecode, a device needs a Java virtual machine, or JVM. The JVM acts as a translator. It reads the universal bytecode and converts it into the specific machine language of the host computer.

JavaUniverse.png
JavaUniverse.png

Because interpreting bytecode can be slow, Java uses a tool called a Just-in-Time (JIT) compiler. This compiler translates bytecode into machine code while the program is actually running. This helps the software execute with much higher performance. Java also manages computer memory automatically through a process called garbage collection. In some languages, programmers must manually clear out old data from the memory. In Java, the runtime environment identifies when an object is no longer being used. The garbage collector then automatically recovers that memory. This prevents many errors, though programmers must still be careful not to keep unnecessary references to objects.

JavaUniverse.png
JavaUniverse.png

Java is organized into different editions for specific tasks. Java Platform, Standard Edition, or Java SE, is used for workstation environments. Java Platform, Enterprise Edition, or Java EE, is built for large internet and distributed environments. Java Platform, Micro Edition, or Java ME, is optimized for devices with limited resources. There is also Java Card, which is designed for smart-cards.

JavaUniverse.png
JavaUniverse.png

The history of Java began in June 1991. James Gosling, Mike Sheridan, and Patrick Naughton started the project at Sun Microsystems. They originally called the language "Oak" after a tree outside Gosling's office. They later changed the name to Java, which comes from coffee grown in Indonesia. The project was first intended for interactive television. However, the digital cable industry was not ready for such advanced technology at the time. Sun released the first public version, Java 1.0, in 1996.

James Gosling 2008.jpg
James Gosling 2008.jpg

Java has changed hands over the years. Sun Microsystems released much of the JVM as free, open-source software in 2007. In 2010, Oracle Corporation bought Sun Microsystems. Oracle now acts as the steward of the technology. While Oracle provides its own HotSpot JVM, the official reference implementation is the OpenJDK JVM. OpenJDK is open-source software used by most developers. It is also the default JVM for almost all Linux distributions.

James Gosling 2008.jpg
James Gosling 2008.jpg

Java remains a massive part of the computing world. It runs on everything from laptops and game consoles to scientific supercomputers and data centers. It was once ranked as the third most popular programming language on GitHub. Developers often rely on Long-Term Support (LTS) versions for stability. Current LTS versions include Java 8, 11, 17, 21, and 25. These versions receive regular maintenance and updates. As of now, Java 26 is the current version.

Duke (Java mascot) waving.svg
Duke (Java mascot) waving.svg

566 words
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File:Duke (Java mascot) waving.svg
Duke (Java mascot) waving.svg
File:James Gosling 2008.jpg
James Gosling 2008.jpg
File:JavaUniverse.png
JavaUniverse.png
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