The content of a website that remains the same across pages is referred to as static content. This could be served from a database as well, but it would be the same across all pages. For instance, the navigation menu, logo of the website, or any other information on the header or footer would not depend on inputs from the visitor. In the following screenshot, the static content is highlighted in yellow and dynamic content is highlighted in red for easy reference.
The content of a website that does not remain constant and changes according to user input(s) is referred to as dynamic content. For instance, in case of a product page, all product details such as Product Name, Price, Quantity, and Description are stored in a database and are fetched when a user is viewing a the webpage of a particular product. Therefore, this content is dynamically generated by the CMS and it changes across products.