The ternary ?: is a short if-then-else:

A ? B : C

# is equivalent to
if ( A ) { B } else { C }
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The advantage is that it's an expression, in contrast to if-else, which is a control structure. So.

print A ? B : C;  #correct

# equivalent if-else?
print if(A){ B }else{ C }; #nope

# does the same, but doesn't mean the same:
if( A ){ print B }
else   { print C }
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HTH. See perlop for further enlightment.

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