What is "<url>http://maven.apache.org</url>" tag under project tag in pom.xml?

Question

For quite some time am using the dependency management tool as Maven. I couldn't understand what is the necessity of url tag in pom.xml under project tag.

<project>
  <modelVersion>4.0.0</modelVersion>

  <groupId>com.mycompany.app</groupId>
  <artifactId>my-app</artifactId>
  <version>1.0-SNAPSHOT</version>
  <packaging>jar</packaging>

  <name>Maven Quick Start Archetype</name>
  <url>http://maven.apache.org</url>

  <dependencies>
    ...
  </dependencies>
</project>

Answer 1

the url gives you information about the project, where the project is hosted

from the documentation (http://maven.apache.org/pom.html):

url: The URL, like the name, is not required. This is a nice gesture for projects users, however, so that they know where the project lives.url: The URL, like the name, is not required. This is a nice gesture for projects users, however, so that they know where the project lives.

Examples

joda-time:

https://github.com/JodaOrg/joda-time/blob/master/pom.xml

  <packaging>jar</packaging>
  <name>Joda-Time</name>
  <version>2.8-SNAPSHOT</version>
  <description>Date and time library to replace JDK date handling</description>
  <url>http://www.joda.org/joda-time/</url>

apache commons-lang: http://svn.apache.org/viewvc/commons/proper/lang/trunk/pom.xml?view=markup

  <inceptionYear>2001</inceptionYear>
  <description>
    Apache Commons Lang, a package of Java utility classes for the
    classes that are in java.lang's hierarchy, or are considered to be so
    standard as to justify existence in java.lang.
  </description>
  <url>http://commons.apache.org/proper/commons-lang/</url>