Every element in HTML is considered a "box," whether it is a paragraph or a <div>, an image, or something else. Starting from outside and moving inward the box contains: (1) the margin, which is the transparent/no-color area outside the element (2) the border that extends around the element, on the outer edge of any padding (3), the padding that exists around the content, inheriting the background color of the content area, and (4) the content surrounded by the padding that is the main focus of the element.