# bitfield format: xxxMMMxx

my @msgs = ( 'a' .. 'i' );
my $msg = $msgs[ ( $bitfield >> 2 ) && 7 ];

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It's also used in doing checksums, hashing, encryption, doing exponent changes in fixed-point arithmetic, quick multiplications and divisions by powers of two, etc, etc.

Update: I missed that you also asked about bitwise operators. They are usually used to extract informations from numbers that contains multiple flags or fields. For example, system returns a number that consists of 3 fields: 

bit15         bit0
|                |
v                v
C SSSSSSS EEEEEEEE

C = Core dumped?
S = Signal that caused program to exit
E = Process's exit code.

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These can be extracted as follows: 

$core_dumped = ($? >> 15) & 1;
$signal      = ($? >> 8) & 127;
$exit_code   = $? & 255

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In reply to Re: Shift Operators And Bitwise Operators by ikegami
in thread Shift Operators And Bitwise Operators by biohisham

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