The provided user interface is designed to view and interact with PDF files in a web browser. Key features include:1. PDF.js viewer for displaying thumbnails of pages, document outline, attachments, and navigation controls.2. Highlighting, matching case, selecting text, and text selection tool options.3. Presentation Mode for viewing the PDF file as a slideshow.4. Open, print, download, and current view options.5. Tools menu with features like rotating, zooming, and page layout options.6. More Information and Less Information buttons offering additional settings and features.7. Close button for closing the PDF viewer.