The ASP.NET MVC Sidebar is an expandable and collapsible component that typically acts as a side container to place primary or secondary content alongside the main content. It provides flexible options that can be shown and hidden based on user interactions. Any type of HTML content or component can be placed in the ASP.NET Core Sidebar for quick access and easy navigation, like quick references, menus, lists, and tree views.

The ASP.NET MVC Sidebar component positions its content to the left or right side of the main content area. This option allows the placement of two sidebars on a page, one on the left and one on the right, to show primary and secondary content simultaneously.

Auto closing the ASP.NET MVC Sidebar component content, makes the main content area more readable.