text: **13.4.1 PDF data**
  
  Portable Document Format (PDF) data is an increasingly common data type that can be 
  archived within Content Manager OnDemand. The following key advantages are available by 
  using this data type as a document format: 
  
  (cid:2) It is a read-only format that does not require any external resources, such as images or 
  fonts. It is self-contained. 
  
  (cid:2) The viewer for PDF can be downloaded at no charge from the Adobe website and the 
  browser plug-ins for PDF are also available at no charge. 
  
  During PDF document creation, resources, such as images and custom fonts, are placed in 
  the data stream once and then referenced many times from within the PDF file. If a large 
  report is produced from many small documents, that report requires only one copy of the 
  resources. 
  
  However, when the PDF is indexed, the PDF Indexer creates many PDF documents from the 
  input file. Each of these documents requires a certain number of PDF structures, which define 
  a document. These documents are concatenated together in the .out file, and then loaded 
  into Content Manager OnDemand as separate documents. Because the resources are 
  extracted and placed into a separate resource file, they are not included in each document. 
  For an illustration of the process, see Figure 13-3. 