Regex : Groups

Use ( ) for groups.

$html =~ (andrew) 
# matches andrew

((andrew)|(john)|(peter)) 
# matches andrew OR john or peter

# the same, but with whhitespace
# m# - use # as the delimiter
# #x - allow whitespace
$html =~ m#
 (
   ( andrew   )  |
   ( peter    )  |
   ( john     )
 )#x;