1. Chapter 6 Text and Multimedia Languages and Properties.. .

2. Introduction Document has given syntax and structure
also has semantics
may have presentation style associated with it
Figure 6.1 depicts all these relationships
document can also have information about itself, called metadata

3. one or more of these elements may be given together
Syntax of document can express different elements such as structure, presentation style, semantics
one or more of these elements may be given together
structural element (e.g. section) can have fixed formatting style

4. Syntax of document can be
implicit in its content
expressed in declarative language or PL
current trend is to use languages
that provide information on document
structure
format
semantics
readable by humans and computers
SGML is one such language

5. Metadata Metadata is data about data
metadata associated with text include
author
date of publication
source of publication
document length (in pages, words, bytes)
document genre (book, article, memo)
Machine Readable Cataloging Record (MARC) is most used format for library records

6. In Web, metadata used for many purposes
cataloging
content rating (e.g. to protect children from reading some type of document)
intellectual property rights
digital signatures (for authentication)
privacy levels (who should/should not have access to document)
application to EC, etc.

7. New standard for Web metadata is Resource Description Framework (RDF)
RDF allows description of Web resources
consists of description of nodes and attached attribute/value pairs
nodes can be any Web resource (any URI), that include URL
attributes are properties of nodes, and their values are text strings or other nodes

8. Text
With the advent of computers, necessary to code text in binary digits
first coding schemes were EBCDIC and ASCII
for internationalization of oriental languages like Chinese or Japanese Kanji, 16-bit Unicode (ISO10616) exists

9. Text Formats No single format for text document
in the past, IR systems would convert document to internal format
cannot change content of document
current IR systems have filters to handle most popular documents, in particular Word, WordPerfect or Framemaker

10. Other text formats for document interchange
Rich Text Format (RTF)
used by word processors and has ASCII syntax
Portable Document Format (PDF)
developed for displaying and printing documents
Multipurpose Internet Mail Exchange (MIME)
used to encode electronic mail