What is the difference between Html4+css2 and HTML5+CSS3? ____html

The HTML5 specification was created by the newly established WHATWG Working Group in 2004, the 2006 World News Consortium joined the HTML, and in 2008 the HTML5 work draft was released, and the XHTML2 Working Group was discontinued in 2009, and 2010 HTML5 began to address practical issues, Gradually the major browser manufacturers began to upgrade their products to support HTML5+CSS3,HTML5 has been continuously improved, 2012 HTML5 completed the preparation of the work, will be released in 2022 HTML5 recommended version;

What is the difference between Html4+css2 and HTML5+CSS3, and what are the advantages of HTML5?

first , HTML5 compatible with the previous HTML4 browser;

second , the new additions to the HTML5 are to track, analyze and generalize existing Web pages and user habits.

Third , the HTML5 specification is based on the user's priority, to improve the efficiency of user development;

Fourth , the HTML5 is more secure; HTML5 introduces a new base-source security model, which is not only easy to use, but also versatile for various APIs.

Fifth , HTML5 performance and content separation;

Sixth , HTML5 to simplify;

A, to replace complex JavaScript code with native capabilities of browsers;

B, simplifying the DOCTYPE;

c, simplified character set declaration;

D, simple and powerful HTML5 API;

Seventh , HTML5 no plug-in paradigm;

There are some problems with the original HTML4 plugin:

A, plug-in installation may fail;

B, plug-ins can be disabled or blocked;

C, the plugin itself has loopholes;

D, Plug-ins are not easy to integrate with other parts of the HTML document because of the boundaries, clipping, and transparency of plug-ins;