The Three Protocol Pillars of the Web

HTTP, HTML, and URLs — the three technologies that define the Web

The Three Pillars

Tim Berners-Lee's 1989 invention combined three technologies that, together, create the Web:

Pillar What It Does Analogy Learn More
HTTP The protocol — how client and server communicate The postal system (how mail gets delivered) HTTP
HTML The content — what gets displayed The letter itself (the message) Tutorial 14
URLs The addresses — where things are The mailing address (where to deliver) URLs

Everything else — CSS, media assets, JavaScript, databases, frameworks, APIs — builds on top of these three. HTML references the included media assets. CSS styles the HTML and media assets. JavaScript adds interactivity. Databases store data. We can go further and add abstractions to hide complexity or frameworks to organize it. But at the core, it's first and foremost HTTP carrying HTML from a URL.

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