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                                             56
     CHAPTER 3                                                                   Syntax



     values. Note that the backslash character is still required as an escape to specify
     unbalanced parentheses or the backslash character itself.


     Hexadecimal Strings

     Strings may also be written in hexadecimal form, which is useful for including
     arbitrary binary data in a PDF file. A hexadecimal string is written as a sequence
     of hexadecimal digits (0–9 and either A–F or a–f ) enclosed within angle brackets
     (< and >):

       < 4E6F762073686D6F7A206B6120706F702E >

     Each pair of hexadecimal digits defines one byte of the string. White-space
     characters (such as space, tab, carriage return, line feed, and form feed) are
     ignored.

     If the final digit of a hexadecimal string is missing—that is, if there is an odd
     number of digits—the final digit is assumed to be 0. For example:

       < 901FA3 >

     is a 3-byte string consisting of the characters whose hexadecimal codes are 90, 1F,
     and A3, but

       < 901FA >

     is a 3-byte string containing the characters whose hexadecimal codes are 90, 1F,
     and A0.


3.2.4 Name Objects

     A name object is an atomic symbol uniquely defined by a sequence of characters.
     Uniquely defined means that any two name objects made up of the same sequence
     of characters are identically the same object. Atomic means that a name has no
     internal structure; although it is defined by a sequence of characters, those
     characters are not considered elements of the name.

     A slash character (/) introduces a name. The slash is not part of the name but is a
     prefix indicating that the following sequence of characters constitutes a name.
     There can be no white-space characters between the slash and the first character

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