HTML can convey much richer information compared to markdown. It can of course do simple document structure like headers and formatting, but it can also represent all sorts of other information such as: Tabular data using tables, Design data with CSS, Illustrations with SVG, Code snippets with script tags, Interactions using HTML elements with javascript + CSS, Workflows using SVG and HTML, Spatial data using absolute positions and canvases, Images using image tags
作者详细列举了HTML相比Markdown的丰富表达能力，包括表格、CSS设计、SVG插图、脚本代码、交互元素、工作流、空间数据和图像等。