Java is platform independent programming language introduced by SunMicrosystems Inc in 1991. It uses a concept called Object Oriented programming called OOPs.
What is platform Independent?
Platform independent means you can develop your program in windows OS and same program can get executed in different operating systems like windows, mac, linux etc.,
Java is a open source programming language, yes what you heard is correct. Its Free!!
Before you start a java program you need to know the below terminologies
- JDK
- JVM
- JRE
Lets discuss about all these components below:
What is JDK?
JDK(Java Development Kit) gives you an environment where you can build and execute your program, It has two things
- JRE
- JVM
What is JRE?
JRE(Java Runtime Environment) helps you to execute your java program in any machine but you can not develop your program
What is JVM?
JVM(Java Virtual Machine) is an interpreter which takes care of running your java program using JDK or JRE
Confusing? Let me put it like this, there are three phases in java
- Development
- Write your java program in .java files
- Compile
- Java compiler generates byte code that is called .class files
- Run
- JVM takes care of running your generated byte code line by line
This is Java basic introduction if you need more details please refer in java oracle documentation below