What does the term 'responsive design' refer to in web development?

The term 'responsive design' in web development refers to a design approach that allows web pages to automatically adapt and adjust their layout and content based on the size and orientation of the device being used to view them. This means that whether a user is accessing a website on a desktop computer, tablet, or smartphone, the content will rearrange itself to provide an optimal viewing experience. Responsive design uses flexible grids, images, and media queries to ensure that elements on the page can scale and reposition dynamically, enabling better usability and readability across various devices.

The other options do not represent the concept of responsive design accurately. Focusing strictly on desktop interfaces limits accessibility and does not account for the growing number of mobile users. Requiring Flash for animations contradicts modern web standards, as Flash is largely obsolete due to compatibility and security issues. Lastly, using only fixed layouts is contrary to the principle of responsive design, which thrives on fluidity and adaptability rather than rigid, unchanging formats.