Overview of Maven concepts, along with examples and commands to illustrate each step:

Project Creation: To create a new Maven project, you can use the mvn archetype:generate command and select a suitable archetype. An archetype is a template for creating a specific type of project. For example:
```
 mvn archetype:generate -DgroupId=com.example -DartifactId=my-project -DarchetypeArtifactId=maven-archetype-quickstart -DinteractiveMode=false
```
This command creates a new Maven project with the specified group ID (com.example) and artifact ID (my-project) using the maven-archetype-quickstart archetype.
Project Structure: The project structure has already been explained in the previous response. Maven follows a standard directory structure for source code, resources, tests, and artifacts.

POM (Project Object Model): The POM is an XML file named pom.xml that contains project configuration, dependencies, build settings, and more.

Here's an example of a simple pom.xml file:

 <project>
     <groupId>com.example</groupId>
     <artifactId>my-project</artifactId>
     <version>1.0</version>
     <packaging>jar</packaging>

     <dependencies>
         <!-- Define project dependencies here -->
     </dependencies>

     <build>
         <plugins>
             <!-- Define build plugins here -->
         </plugins>
     </build>
 </project>

Dependency Management: Maven makes it easy to manage project dependencies. You can add dependencies to the <dependencies> section of your pom.xml file. Maven automatically downloads the required dependencies from remote repositories.

Example dependency entry in pom.xml:
```
 <dependencies>
     <dependency>
         <groupId>org.slf4j</groupId>
         <artifactId>slf4j-api</artifactId>
         <version>1.7.32</version>
     </dependency>
 </dependencies>
```
Building the Project: Maven provides a set of built-in lifecycle phases for building, testing, and packaging projects. Common Maven commands include:
- mvn clean: Cleans the target directory.
- mvn compile: Compiles the source code.
- mvn test: Runs tests.
- mvn package: Packages the compiled code (e.g., JAR, WAR).
- mvn install: Installs the project artifact to the local repository.
- mvn deploy: Deploys the project artifact to a remote repository.
Running Goals: You can also run specific Maven goals using the mvn command. For example:
```
 mvn clean compile
 mvn test
 mvn package
```

Running Plugins: Maven plugins enhance the build process. For instance, the maven-compiler-plugin helps compile code, and the maven-surefire-plugin handles test execution.

Example plugin configuration in pom.xml:

 <build>
     <plugins>
         <plugin>
             <groupId>org.apache.maven.plugins</groupId>
             <artifactId>maven-compiler-plugin</artifactId>
             <version>3.8.1</version>
             <configuration>
                 <source>1.8</source>
                 <target>1.8</target>
             </configuration>
         </plugin>
     </plugins>
 </build>

External Repositories: Maven downloads dependencies from remote repositories. You can configure additional repositories in your pom.xml file.

Example repository configuration:

 <repositories>
     <repository>
         <id>central</id>
         <url>https://repo.maven.apache.org/maven2</url>
     </repository>
     <!-- Other repositories -->
 </repositories>

Running Custom Commands: You can run custom Maven plugins or commands using the mvn command, referencing the plugin's goal.

For example, if you have a custom plugin named my-plugin with a goal named custom-goal, you can run it like this:
```
 mvn my-plugin:custom-goal
```