Validation (XHTML 1.0 Transitional): A newer construct is recommended.

XHTML 1.0 Transitional

Elements	Newer Constructs
<menu />	Use another list type.
<u />	Use CSS property “text-decoration” and set its value to “underline”.
<s />	Use CSS property “text-decoration” and set its value to “line-through”.
<strike />	Use CSS property “text-decoration” and set its value to “line-through”.
<basefont />	Use CSS styling and set the “font-family” property to desired font.
<font />	Use CSS styling to set the property of the element, such as a DIV or SPAN.The CSS properties include:   color font-family font-size text-decoration text-align text-indent text-transform font-weight
<applet />	Use the <object /> tag
<isindex />	Use the <input /> tag
<i />	Use the <em /> tag
<b />	Use the <strong /> tag
Elements / Attributes	Newer Constructs
Iframe
name	Use the ID attribute
align	Use the CSS property “text-align”
body
background	Use the CSS property “background-image” or “background”.
bgcolor	Use the CSS property “background-color” or “background”.
text	Use the CSS property “color” for the “body” style
link	Use the CSS section “a:link” and set the property “color”.
vlink	Use the CSS section “a:visited” and set the property “color”.
alink	“a:hover” and set the property “color”.
div / p / h1…h6
align	Use the CSS property “text-align”.
ul / ol / li
type	Use the CSS property “list-style-type” or “list-style”.
compact	This attribute has been removed from the HTML DOM 1.0
hr
align	Use the CSS property “text-align”.
noshade	Use the CSS property “color”.
size	Use the CSS property “height”.
width	Use the CSS property “width”.
pre
width	Use the CSS property “width”.
name	Use the attribute “id”.
br
clear	Use the CSS property “clear”.
object
align	Use the CSS property “vertical-align” and “text-align” in the parent tag
border	Use the CSS property “border”.
hspace	Use the CSS property “padding”.
vspace	Use the CSS property “padding”.
img
name	Use the attribute “id”.
align	Use the CSS property “vertical-align” and “text-align” in the parent tag
border	Use the CSS property “border”.
hspace	Use the CSS property “padding”.
vspace	Use the CSS property “padding”.
map
name	Use the attribute “id”.
input
align	Use the CSS property “vertical-align” and “text-align”
legend
name	Use the attribute “id”.
table
align	Set table’s CSS properties left-margin and right-margin at “auto” for centering, or right-margin to 0 for right alignment, or the left-margin to 0 for left alignment.
bgcolor	Use the CSS property “background-color”.
tr
bgcolor	Use the CSS property “background-color”.
td, th
nowrap	Use the CSS property “word-wrap”.
bgcolor	Use the CSS property “background-color”.
width	Use the CSS property “width”.
height	Use the CSS property “height”.