Many outputs are produced as a collection of several files, others may only produce a single file. A chunk is a generic, informal term for a portion of an output, typically a single file. This is given as a level, see Section 26.2 for more about levels. The specification is in the attribute
/publication/common/chunking/@level
with a whole number as the value (generally 0 is allowed). This is critical for the construction of HTML output, and ignored for LaTeX output.
