content/markdown/glossary.md

## Glossary

This document describes some of the most common terms encountered while
using Maven. These terms, that have an explicit meaning for Maven, can
sometimes be confusing for newcomers.

-   **Project**: Maven thinks in terms of projects. Everything that you
    will build are projects. Those projects follow a well defined
    "Project Object Model". Projects can depend on other projects, in
    which case the latter are called "dependencies". A project may
    consistent of several subprojects, however these subprojects are
    still treated equally as projects.
-   **Project Object Model (POM)**: The Project Object Model, almost
    always referred as the POM for brevity, is the metadata that Maven
    needs to work with your project. Its name is "project.xml" and it is
    located in the root directory of each project.
-   **Artifact**: An artifact is something that is either produced or
    used by a project. Examples of artifacts produced by Maven for a
    project include: JARs, source and binary distributions, WARs. Each
    artifact is uniquely identified by a [group id](#GroupId) and an
    artifact ID which is unique within a group.
-   **GroupId**: A group ID is a universally unique identifier for a
    project. While this is often just the project name (eg.
    `commons-collections`), it is helpful to use a fully-qualified
    package name to distinguish it from other projects with a similar
    name (eg. `org.apache.maven`).
-   **Dependency**: A typical Java project relies on libraries to build
    and/or run. Those are called "dependencies" inside Maven. Those
    dependencies are usually other projects' JAR artifacts, but are
    referenced by the POM that describes them.
-   **Plug-in**: Maven is organized in plugins. Every piece of
    functionality in Maven is provided by a plugin. Plugins provide
    goals and use the metadata found in the POM to perform their task.
    Examples of plugins are: jar, eclipse, war. Plugins are primarily
    written in Java, but Maven also supports writing plug-ins in
    Beanshell and Ant Scripting.
-   **Mojo**: A plugin written in Java consists of one or more mojos. A
    mojo is a Java class that implements the
    org.apache.maven.plugin.Mojo interface. This means that a mojo is
    the implementation for a goal in a plugin.

-   **Repository**:

    Refer to [Introduction to
    Repositories](./guides/introduction/introduction-to-repositories.html)

-   **Snapshots**: Projects can (and should) have a special version
    including `SNAPSHOT` to indicate that they are a "work in progress",
    and are not yet released. When a snapshot dependency is encountered,
    it is always looked for in all remote repositories, and downloaded
    again if newer than the local copy.

    The version can either be the string `SNAPSHOT` itself, indicating
    "the very latest" development version, or something like
    `1.1-SNAPSHOT`, indicating development that will be released as 1.1
    (i.e. newer than 1.0, but not yet 1.1).

-   **APT**: APT is a wiki-like format of documentation that Maven
    currently understands.

    For information on how to create APT files, refer to the [Guide to
    creating a site](./guides/mini/guide-site.html) document.

-   **XDoc**: XDoc is the format of documentation that Maven currently
    understands. It is quite simple, and allows embedding XHTML within a
    simple layout that is transformed into a uniform site.

    For information on how to create XDoc files, refer to the [Guide to
    creating a site](./guides/mini/guide-site.html) document.