Views Documentation

Views is a powerful query builder for Drupal that allows you to fetch and present lists of content (posts/nodes) to the user in ways that are tailored to your site and your content. Whereas many of the existing tools to do this are more straightforward and easy to use, they also dictate the terms.

For example, taxonomy lists will only display content for the given taxonomy terms, and it will only display them in reverse chronological order. If you want to display them alphabetically, taxonomy.module provides no tool to do this by itself.

The tracker module will display all of your sites content, also sorted in reverse chronological order. But if you want it to display only forum posts, tracker.module provides no tool to do this by itself.

These are just two of the most obvious tasks for Views, but there are many, many more.