HTML (Layout) Tags and their meanings

More info (attributes, rules, etc): http://www.w3schools.com/tags/default.asp

Tagname Stands for Default Display Notes
<div> division block Generic way to group contents. Can pretty much contain anything.
<span> er, span inline Generic way to group inline contents.
<h1> to <h6> headline 1-6 block Headlines - with varying degrees of heirarchical importance (1=topmost, 6-bottomest).
<a> anchor inline (text-decoration: underline) Anchors are what makes the www go 'round. With their very significant "href" and "name" attributes, the anchor is handy. Has some nifty CSS pseudo selectors (:visited, :link, :hover)
<table> um, table block Tables are for the display of data sets, with a header row with labels for the columns followed by rows of data. Ideally, tables should not be used for page layout.
<ul> unordered list block A list of items whereby their order does not have meaning for the contents. Exmaples: FAQ, bullet points, etc...
<ol> ordered list block A list of items whereby their order is meaningful. Examples: top ten list, 2008 OKRs, search results, etc...
<li> list item block Designates list items inside of ul and ol.
<dl> definition list block Contains terms and their definitions, generally.
<em> loud inline (font-style: italic) In the context of the things around it, the contents of the em tag are somewhat more important. "Once more, with feeling."
<strong> louder inline (font-weight: bold) In the context of the things around it, the contents of the em tag are very important.
<form> form block For Actions POST/GET
<fieldset> set of fields block A fieldset is used to group logically relevant fields together in a form. Maybe you have a long form with three sections? Or a bunch of checkboxes that all should go together? Then the fieldset is for you!
<label> field label inline Used in a form, denotes the text label for the input. Has the important "for" attribute. Helps with accessibility and usability in forms.

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