^   beginning of line 
      if ^ is the first character in the pattern
     Sample: ^subj:    line start with 'subj:'

$   end of line 
    if $ is the last character in the pattern.  
    The result doesn't contain return code. 
     To contain return code, specify '\r' instead.
     Sample:  ^$    blank line (without return code)
     Sample:  ^\r   blank line (with return code)

.    any character 
     Sample: a.d 
     Starts with 'a' follwed by any character and
     ends with 'd'.  It matches 'and', 'add', 'dandy'.

*  zero or more specified patterns
     Sample:    an*d
     Starts with 'a' follewed by zero or more 'n's
     and ends with 'd'.  It matches 'and', 'advance', 
     'add'.

*? zero or more specified patterns and
     matches the minimum number of times
     Sample: If you search ".*bbb" in the text

    "aaa bbb bbb bbb cccc", 
      the string "aaa bbb bbb bbb" will be returned.
      But if you search ".*?bbb" in it,
      the string "aaa bbb" will be returned.

+  one or more specified patterns
     Sample:    an+d
     Starts with 'a' follewed by one or more 'n's
     and ends with 'd'.  It matches  'and', 'annd' but
     not 'advance', 'add'.

+? one or more specified patterns and
     matches the minimum number of times

?   zero or one specified pattern
     Sample:    an?d
     Starts with 'a' follewed by zero or one 'n'
     and ends with 'd'.  It matches  'and', 'add' but
     not  'annd'.

??  zero or one specified pattern and 

matches the minimum number of times

\   escape
     Use escape pairs when you want to express
     characters that have special meaning in regular
     expression such as '^', '$', '\'.
     Sample:   \^   character '^' as data
     Sample:   \\   character '\' as data
     Sample:   \$   character '$' as data
     Sample:   \*   character '*' as data
     Sample:   \+   character '+' as data

     Use escape pairs to express non-printing
     characters as follows.
     '\t' =TAB, '\r' =CR, '\n' =LF, 
     '\s' =SPACE, '\b' =BS,
     '\d' =[0-9]  (digits)
      '\w' =[A-Za-z_]  (alphabets & '_')
    
     To express characters as hex-decimal codes,
     use '\h' follewed by its hex-decimal codes.
     Sample:   \h20        space (one byte)
     Sample:   \h8140   two bytes kanji space
     
[ ]  character class
     Set and range pattern matches of some characters.
     You can use also 2 byte characters as its components.
     Use '-' to express  the range pattern. 
     Use '^' to express the exception set.
     Sample:   [abc]    any one of characters a, b, c.   
     Sample:   [A-Z]   any one of characters in the 
                                   A to Z, capital alphabet range.
     Sample:  [^a-z]  any one of characters excluding
                                   lower-case alphabets.
     Sample:  [a-xABC] 
                                  any lower-case alphabet character
                                  between a to x and characters A, B, C.
     Sample:  [\t\s\h8140]+$
                                  one or more continuous characters of 
                                  tab, space or kanji space characters
                                  at the end of a line.

   group
      Use  to divide find strings into desired groups that
      are used in replacement strings.  You can also use \( and
      \) marks for  and  marks.
      
      For example, person's name is expressed as follows.
      
      [A-Z][a-z]+\s+[A-Z][a-z]+

       First group [A-Z][a-z]+ is the given name.
       Second group [A-Z][a-z]+ is the family name.

      First group is expressed using  \1 in the replacement
      string, second group is \2. 

      To replace names using 'family name first styles', 
      specify following replacement string.
      
      \2, \1
      
      Family name is first, followed by a comma and the given
      name.
      
|   multiple search
      You can find multiple strings at once. Use | to specify multiple 
      find strings as follows.
      
      <expression1> | <expression2> | <expression3>...
      
      You can't use  | mark in the character class [] or group .