HTML ships a vocabulary most developers skip: nav, main, article, aside, figure, button. Each carries built-in meaning and behavior — a button is focusable and activates on Enter for free; a div is none of that until you rebuild it. Semantic markup is the version of the page machines read.
The beneficiaries compound: screen readers get landmarks to navigate by, search engines get a content outline, answer engines get paragraphs that stand alone, and the developer gets accessibility that did not cost extra. Divs-and-spans is not wrong HTML; it is just a page that explains nothing about itself.
Related terms
ARIA
Accessible Rich Internet Applications — attributes that tell assistive technology what your markup means when HTML alone cannot.
WCAG
The Web Content Accessibility Guidelines — the standard that defines what makes web content usable by people with disabilities; AA contrast is 4.5:1 for body text.
SEO
Search engine optimization — making pages findable, indexable and worth ranking: technical health plus content people actually want.
The bench this belongs to
Full-stackIf you can describe it, we can build it. React and Next.js on the front, Python or Node behind, Postgres underneath, shipped to somewhere you can afford to run.
