<span style="font-family: Ubuntu, sans-serif; font-size: 16px; line-height: 23.2px;">All content on a Drupal website is stored and treated as "nodes". A node is any piece of individual content, such as a page, poll, article, forum topic, or a blog entry. For example a newspaper website, each articles is a node, a node can have different fields like an image, a video, text etc. </span><span style="line-height: 1.42857;">This tutorial explains the concept of node in detail - https://www.drupal.org/docs/7/nodes-content-types-and-fields/about-nodes </span>