.jpg (Joint Photographic Experts Group)
The .jpg format is a widely used method of lossy compression for digital images, especially for those images produced by digital photo. The compression level can be adjusted, allowing a selectable balance between storage size and image quality. jpg is commonly used for storing and transmitting photographs on the World Wide Web, and it's also a standard format used by digital cameras and other photographic image capture devices.

HTML (Hypertext Markup Language) is the standard markup language used for creating web pages and web applications. It describes the structure of a web page semantically and originally included cues for the appearance of the document. HTML provides the basic building blocks for webpages, allowing for the integration of text, images, multimedia, and other elements. HTML files are essential for the World Wide Web and are interpreted by web browsers to display content.