+@node Creating output file metadata
+@subsection Creating output file metadata
+
+@cindex PDF metadata
+@cindex MIDI metadata
+
+In addition to being shown in the printed output, @code{\header} variables
+are also used to set metadata for output files. For example, with PDF
+files, this metadata could be displayed by PDF readers as the
+@code{properties} of the PDF file. For each type of output file, only the
+@code{\header} definitions of blocks that define separate files of that
+type, and blocks higher in the block hierarchy, will be consulted.
+Therefore, for PDF files, only the @code{\book} level and the top level
+@code{\header} definitions affect the document-wide PDF metadata, whereas
+for MIDI files, all headers above or at the @code{\score} level are used.
+
+For example, setting the @code{title} property of the @code{header} block
+to @q{Symphony I} will also give this title to the PDF document, and use
+it as the sequence name of the MIDI file.
+
+@example
+\header@{
+ title = "Symphony I"
+@}
+@end example
+
+If you want to set the title of the printed output to one value, but have the
+title property of the PDF to have a different value, you can use
+@code{pdftitle}, as below.
+
+@example
+\header@{
+ title = "Symphony I"
+ pdftitle = "Symphony I by Beethoven"
+@}
+@end example
+
+The variables @code{title}, @code{subject}, @code{keywords},
+@code{subtitle}, @code{composer}, @code{arranger}, @code{poet}, @code{author}
+and @code{copyright} all set PDF properties and can all be prefixed with
+@q{pdf} to set a PDF property to a value different from the printed output.
+
+The PDF property @code{Creator} is automatically set to @q{LilyPond} plus
+the current LilyPond version, and @code{CreationDate} and @code{ModDate} are
+both set to the current date and time. @code{ModDate} can be overridden by
+setting the header variable @code{moddate} (or @code{pdfmoddate}) to a
+valid PDF date string.
+
+The @code{title} variable sets also the sequence name for MIDI. The
+@code{midititle} variable can be used to set the sequence name
+independently of the value used for typeset output.