In web design, a sidebar is a vertical column or section located on the side of a web page next to the main content area. It often contains supplementary information, navigation links, social media icons, advertisements or other content that is related to the main content of the page but not essential to the page’s primary purpose. Sidebars can be fixed or scrollable, and their content can vary depending on the specific page or section of the website. The use of sidebars is common in many types of websites, including blogs, news sites and e-commerce platforms.