# JDK, JRE and Eclipse JRE (Java Runtime) is needed for _running_ Java programs. JDK (Java Development Kit), which includes JRE plus the development tools (such as compiler and debugger), is used for _writing_ as well as _running_ Java programs. We use OpenJDK, the open source JDK so we are not tied to Sun's licensing. Eclipse is an Integrated Development Environment, a set of tools to make programming easier than simply using the DK.  There are many other IDEs you can choose from such as Netbeans  and IntelliJ IDEA.  They all have their strengths. You Can Download All the Things You Need for Developing Java Programs for Free. We use the Eclipse IDE. It's available for PC, Apple and Linux # Install JDK You must install the JDK first. We are currently using Temurin OpenJDK 17. Follow the link for the download: https://adoptium.net/en-GB/temurin/releases/ In the drop downs, choose version 17- LTS and package type JDK. You will probably choose Windows as the Operating System and x64 as the Architecture. Chose the msi (Microsoft Installer) package. This will install everything for you in the correct place. # Install the Eclipse IDE for developers We are currently using Eclipse 2023-06 R for developers, which is available here: https://www.eclipse.org/downloads/packages/ Note we are using the IDE for Developers not for Enterprise Java and Web. You will probably choose the Window x86_64 download. You don't have to donate. The file will download as a zip package. Unzip it to the Program Files directory on your C: Drive. The executable is in the root of the Eclipse folder. When you run Eclipse for the first time you will be asked to select a directory as a workspace. This will be where all your files are stored. Choose somewhere sensible and then check the use as default box