What's the difference?
Most sites simply say "Use this when you want really clean structural mark-up, free of any tags associated with layout".

I get this error on the w3c validator:
Error: document type does not allow element "img" here; missing one of "p", "h1", "h2", "h3", "h4", "h5", "h6", "div", "address", "fieldset", "ins", "del" start-tag

Must I put a <img> in a <p> to conform to strict standards?