Preservation of digital objects through canonical representations (simplified versions) of those objects. An important application of canonicalization is ensuring that digital signatures don't "break" when data is moved from one context to another.

• Canonicalization: A Fundamental Tool to Facilitate Preservation and Management of Digital Information - Clifford Lynch, D-Lib Magazine, September 1999
• Canonical XML, Version 1.0 - (W3C Recommendation) designed to encode the logical structure of XML documents so that two XML documents whose Canonical-XML form is identical will be considered equivalent for the purposes of many applications, particularly for ensuring the integrity of data traveling between XML processors for applications such as electronic commerce
• Exclusive XML Canonicalization, Version 1.0 - (W3C Working Draft as of 2002-01-03) provides a method to exclude ancestor context from the canonicalized form of a subset of an XML document, particularly where a digital signature over an XML subdocument is needed which will not break when that subdocument is removed from its original document and/or inserted into a different context