  person,    $person,     
  echo   .    $ -
 ,  $person    ,   -
      echo.   echo  ,
   ,    ,     .  -
       person.

     , 
  $:

$ echo $person

alex

$ echo "$person"

alex

$ echo '$person'

$person

$ echo \$person

$person

     ,     
 (\)  .

      ,  
    ,    
       .  -
  ,     TAB,    
 .      ,   -
     ,      :

$ person="alex  jenny"
$ echo $person

alex  jenny

         -
,   TAB     .   -
    ,  echo    
        :

$ ="      "
$ echo $person

  
$ echo "$person"
      

          
         . 
     ( *  ?), 
   .

        memo
  alex*. Bourne Again Shell   , 
bash     (.  "    -
 "  7)    .  
    .      Bourne
Again Shell  ,    .  -

304                                       III.   Red Hat Linux