26. Use a class 1. The style is used in various places throughout the document. 2. The style is very general. <span class= " alert "> <span class= " alert error "> <h2 class= " headline ">
27. Use an ID 1. The style is only used once ever in the document. 2. The style is specific to a certain area of the document. <div id= " header "> <body id= " home "> <body id= " home page ">
28. ID and class can be friends <li id= " home " class=" current ">
29. Beautiful HTML = Separate presentation from the content the content the content
39. Use <!--comment --> to create separated code blocks to create separated code blocks
40. <!-- header --> <div id="header"> ... <div> <!-- end of header --> <!-- main --> <div id="main"> ... <div> <!-- end of main -->