New features: HTML5 is no longer a subset of SGML, but more about graphics, location, storage, multitasking, etc

New selector document. QuerySelector, document. QuerySelectorAll Drag release (Drag and drop) API streaming video and audio local storage and localStorage SessionStorage Offline application Manifest desktop notification Notifications semantic tags article, footer, Header, nav, Section enhancement form control Calendar, Date, Time, Email, URL, and Search Geolocation Multi-task Webworker Full-duplex communication protocol Websocket History Management History Cross-domain resource sharing (CORS) Access-control-allow-origin page visibilitychange event visibilitychange cross-window communication PostMessage Form Data object painting canvas

Removed elements:

Pure performance elements: Basefont, Big, Center, FONT, S, Strike, TT, U Elements that negatively affect usability: Frame, Frameset, Noframes

<meta name="viewport" The content = "width = device - width, initial - scale = 1.0, the minimum - scale = 1.0, the maximum - scale = 1.0, user - scalable = no" / > <! -- width Sets the viewport width as a positive integer, or the string 'device-width'. Device-width specifies the device width. You don't need to set the default initial-scale scale (the initial scale) to a number, you can use the decimal minimum-scale to allow the user to scale at the minimum, you can use the decimal maximum-scale to allow the user to scale at the maximum, which is a number, Scalable scalable with decimal user-scalableCopy the code