I'm sure this is overkill ( I saw others using regexs so I thought I'd go all out. ;)), but this is how I like to do command line driven programs like this. Basically I'm creating a lookup table with the %actions hash. When someone enters their choice, it checks to see if that choice exists in the lookup table, if it does, it'll execute the sub reference that the lookup table points to. If the choice does not exist in the lookup table, it goes on to throw the error and starts the loop over again. While I understand you're new to perl, this may give you a little something to chew on while you learn. :-D

use strict;

my %actions =     (
                    'y' => \&calcHourly,
                    'h' => \&calcYearly,
                    'q' => sub { exit(); },
                );
                
while ( 1 )
{
    print "\nEnter y (or) h (or) q to calculate Yearly salary(y) or Ho
+urly rate(h) q to Quit: ";
    chomp( my $myAction = <STDIN> );
    
    if ( exists $actions{ $myAction } )
    {
        $actions{ $myAction }->();
        next;
    }

    print "\nError: \"$myAction\" is not a valid choice, please try ag
+ain\n\n";
}

sub calcHourly
{
    print "Enter your hourly rate: ";
    chomp ( my $hourrate = <STDIN> );
    my $yearrate = ( $hourrate * 40 ) * 52;
    print("\nYour Annual salary is: \$$yearrate\n\n");
}

sub calcYearly
{
    print "Enter your yearly salary: ";
    chomp ( my $yearrate = <STDIN> );
    my $hourrate = ( $yearrate / 52 ) / 40;
    print("\nYour hourly rate is: \$$hourrate\n\n");   
}
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(oops, replied to the wrong one, doh!)