Update README.md

README.md

@@ -7,3 +7,29 @@ Jupiter using [Gradle's native JUnit Platform support], Gradle's Groovy DSL
 and code and tests written in Java.
 
 [Gradle's native JUnit Platform support]: https://docs.gradle.org/current/userguide/java_testing.html#using_junit5
+
+# Overview 
+
+The goal of this document is to provide comprehensive reference documentation for programmers writing tests, extension authors, and engine authors as well as build tool and IDE vendors.
+
+# JUnit 5
+
+## What is JUnit 5?
+
+Unlike previous versions of JUnit, JUnit 5 is composed of several different modules from three different sub-projects.
+
+JUnit 5 = JUnit Platform + JUnit Jupiter + JUnit Vintage
+
+The JUnit Platform serves as a foundation for launching testing frameworks on the JVM. It also defines the TestEngine API for developing a testing framework that runs on the platform. Furthermore, the platform provides a Console Launcher to launch the platform from the command line and a JUnit 4 based Runner for running any TestEngine on the platform in a JUnit 4 based environment. First-class support for the JUnit Platform also exists in popular IDEs (see IntelliJ IDEA, Eclipse, NetBeans, and Visual Studio Code) and build tools (see Gradle, Maven, and Ant).
+
+JUnit Jupiter is the combination of the new programming model and extension model for writing tests and extensions in JUnit 5. The Jupiter sub-project provides a TestEngine for running Jupiter based tests on the platform.
+
+JUnit Vintage provides a TestEngine for running JUnit 3 and JUnit 4 based tests on the platform.
+
+![JUnit5](https://static.packt-cdn.com/products/9781787284661/graphics/f33bca9e-f503-4cdc-aa20-d90ca0d07e74.png)
+
+## Supported Java Versions
+
+JUnit 5 requires Java 8 (or higher) at runtime. However, you can still test code that has been compiled with previous versions of the JDK.
+
+