PDFs have a few notable disadvantages over HTML

• The tend to be larger and take longer to download
• They require an additional piece of software to open and so again it takes longer for the user to 'get' the content
• Early versions of PDFs were inaccessible, many moves have been successufully made to increase the accessibility of PDFs in recent years, but they are still not as accessible as HTML.

PDFs have a few advantages over HTML:

• The text and images are all embroiled into one file, so they are easier to pass text and image rich content.
• They provide an accurate screen representation of a paged media, and are useful when such is a requirement.
• They are quicker to produce.

To help you decide whether your document would work best as HTML or PDF we've produced a little test, please try this tool to determine whether your document should be HTML or PDF.

A well produced PDF should be accessible and navigable, most of the work required to produce a good PDF must be done in the source file, for example in Word.

• The ideal word document [120KB]
• The ideal PDF document [120KB]

These documents explain the standards relevant to PDFs and are made using those same standards.