Variables

• $ - Scalar
  $myvalue
   
• @ - Array
  @myarray = ("value1", "value2", value3", "value4");
  $myarray = @myarray[2]; - $myarray contains "value3"
   
• % - Hash
  %myhash = (
  "Mon" => "Monday",
  "Tue" => "Tuesday",
  );
  $day = $myhash{"Mon"}; - $day contains "Monday".
   

Subroutines

• & - Subroutine
  

  sub ADDONE
  {
  $value = $_[0];
  $newvalue = $value ++ ;
  return $newvalue;
  }
  
  $numberplusone = &ADDONE($number);
  

Loops

• for
• while
• foreach

Control Structures

• if (condition)
  {statement....}
  else
  {statement....}
  
  
• unless (condition)
  {statement....}
  
  

Example:-

my $debug='1';

if ($debug){print "Debug mode is on. \n";}