Web, documents and technology
Viewport
In short and in plain language
The viewport is the part of the web page that you can see right now.
Its width decides how the page arranges its parts.
If you zoom in a lot in the browser, this part gets narrower. The page should then rearrange itself.
Definition
The viewport is the visible area of a web page in the browser window or on a smartphone screen. Its width determines how a page arranges its content. When someone zooms in the browser, the viewport becomes narrower in CSS pixels and the page should then rearrange its content.