Steve writes:

# I am new to the Ruby. I try to test the Ruby/Tk and enter the follow
# program.
<...>
# Could anyone tell me what's the
# difference between the two ways of calling pack. Thanks

I'm leaving, but I'm sure someone can give you a more complete and elegant 
explanation in a few hours. However, for starters,

    '=>' is a hash literal.
    ';' is a line or expression separator.

Conrad Schneiker
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