When talking about Drupal, many people focus on the modules that are available to create new functionality.
However, a focus on modules provides an incomplete picture. Over the years, Drupal has evolved away from a model of "one module delivers one feature" to a model where new functionality is created by using features contained within two or more different modules.
For site builders, this means that the work of building and maintaining Drupal sites is more akin to a chef: delivering new functionality is a recipe that pulls from multiple ingredients (modules).
And, just as there are many ways to make a good chili, there are many ways to build similar functionality in Drupal.