The Most Important Differences from HTML - HTML vs. XHTML - Horje

<!DOCTYPE> is mandatory
The xmlns attribute in <html> is mandatory
<html>, <head>, <title>, and <body> are mandatory
Elements must always be properly nested
Elements must always be closed
Elements must always be in lowercase
Attribute names must always be in lowercase
Attribute values must always be quoted
Attribute minimization is forbidden

Category:	Web Tutorial
Sub Category:	HTML vs. XHTML
Uploaded by:	Admin

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https://develop.horje.com/learn/1434/reference