The <alternatives> element holds multiple, logically equivalent (substitutable) versions of the same information object. The typical case is a graphic (<graphic>) which is provided in multiple formats (such as a TIF, a JPEG, and an SVG image) or in multiple resolutions. These various formats offer processing alternatives for use by production personnel or by software in presenting the work to the user. For example, a high-resolution TIF image may be included and designated for use in printing while the same image, provided as a lower-resolution JPEG file, may be designated for use in web display.

Other potential use cases include:

• An equation (<disp-formula> or <inline-formula>) that is available as an image as well as a MathML-tagged version; or
• A table (<table-wrap>) for which both NISO JATS XHTML-inspired Table tagging and an image have been provided.

Similarly, a table (<table-wrap>) may be provided in multiple formats; for example, the table below has three alternative formats: an XML-tagged table, the equivalent image file, and a textual version with the tabular look created by lines and spacing.

...
<table-wrap>
  <object-id>...a DOI...</object-id>
  <alternatives>
    <table frame="box" rules="all" cellpadding="5">...an XHTML-inspired formatted table...</table>
    <preformat>...a tabular form with spaces and tabs...</preformat>
    <graphic xlink:href="tab437.jpg">...a JPEG of the same table...</graphic>
  </alternatives>  
</table-wrap>
...

The element <alternatives> may contain graphical alternatives, XML-tagged alternatives, and one or more alternatives that contain text characters. For example, the alternatives within an equation might be a JPEG image of the equation, an XML equation tagged in MathML, and a plain text equivalent equation such as a + b = c. The <textual-form> element can be used inside <alternatives> to hold such plain text version alternatives.

Where to use <alternatives> — The <alternatives> element contains processing alternatives for a single display object such as a graphic or a table. Typical uses include:

Where NOT to use <alternatives> — The element <alternatives> should not be used to tag multiple versions of content that are intended for different audiences or document-building uses.

Do not use <alternatives> for:

These intentional/semantic alternatives are different from the case of multiple formats of the same graphic, in part because there is a structural difference; for example, a given section does or does not contain this boxed-text. There is also a difference in complexity between this case and that of the multiple graphic formats, in that software can pick one alternative graphic based on external factors, whereas, for the semantically distinct objects, the software must build a different structural tree.

JATS provides the @specific-use attribute to record semantic or intentional distinctions, for example, that certain paragraphs are only for print:

<p specific-use="print-only">See the latest updates on our website:
 http://www.mulberrytech.com</p>

This leaves the burden of how to treat these similar-content objects for display to the local processor.

The @specific-use attribute can be placed on all the block-level structures, that is, on paragraphs, figures, sections, and all the block display objects. There is no recommended set of values, but publishers have used “print-only”, “web-only”, “online-only”, “voice-only”, “specific-product-name”, etc.