"Difference Between" or "the difference between"

What is the proper title for the article which compares two things -
"difference between" or "the difference between"
eg :
"difference between alligator and crocodile" or
"the difference between alligator and crocodile"

Thanks in advance

Quote:

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Originally Posted by cherran

What is the proper title for the article which compares two things -
"difference between" or "the difference between"
eg :
"difference between alligator and crocodile" or
"the difference between alligator and crocodile"

Thanks in advance

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The difference between alligators and crocodiles.

Is it possible to explain why they should be plural?