Maven is a Java development toolkit that allows you to manage a project's build, reporting, and documentation more easily. It does this by using a
pom.xml file in the root of your project directory. More information about Maven specifically can be found on the Apache Maven website.
An Aion archetype for Maven is available. This allows you to quickly start a project and interact with the Aion Virtual Machine (AVM) from your local computer. This archetype also allows your easily deploy your contract to the Aion network, as well as interact with contracts already on the network.
The Aion4j archetype is a template project that you can build on top of to create your own project. It comes with a
HelloWorld.java contract and test.
To quote the Apache Maven website:
"[an] archetype is a Maven project templating toolkit. An archetype is defined as an original pattern or model from which all other things of the same kind are made." - Introduction to Archetypes
More information on Maven archetypes specifically can be found on the Apache Maven website.