Maven by Example

1.5. Conceptual Model of a "Project"

Maven maintains a model of a project. You are not just compiling source code into bytecode, you are developing a description of a software project and assigning a unique set of coordinates to a project. You are describing the attributes of the project. What is the project’s license? Who develops and contributes to the project? What other projects does this project depend upon? Maven is more than just a "build tool", it is more than just an improvement on tools like make and Ant, it is a platform that encompasses a new semantics related to software projects and software development. This definition of a model for every project enables such features as:

Dependency Management
Because a project is defined by a unique set of coordinates consisting of a group identifier, an artifact identifier, and a version, projects can now use these coordinates to declare dependencies.
Remote Repositories
Related to dependency management, we can use the coordinates defined in the Maven Project Object Model (POM) to create repositories of Maven artifacts.
Universal Reuse of Build Logic
Plugins contain logic that works with the descriptive data and configuration parameters defined in Project Object Model (POM); they are not designed to operate upon specific files in known locations.
Tool Portability / Integration
Tools like Eclipse, NetBeans, and IntelliJ now have a common place to find information about a project. Before the advent of Maven, every IDE had a different way to store what was essentially a custom Project Object Model (POM). Maven has standardized this description, and while each IDE continues to maintain custom project files, they can be easily generated from the model.
Easy Searching and Filtering of Project Artifacts
Tools like Nexus allow you to index and search the contents of a repository using the information stored in the POM.