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- [Instructor] In this video,
I'd like to demonstrate

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the comparison operators for strings.

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But first, I'd like to just remind you

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that when you're doing
string comparisons in Python,

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it's lexicographical comparisons,

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that is the underlying numeric values

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of the characters are
what are being compared.

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So you may recall that we
introduced the ord function

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previously, the built-in function ord,

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which simply returns for a character

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the corresponding numeric value.

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So here we have the capital letter A

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and the lowercase letter a

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and we just wanted to show you

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that the capital letter
has a smaller value

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than the lowercase letter,

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because that's going to
affect the comparisons

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that we're going to do in
the next several expressions.

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So you can compare any two strings

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using the comparison
operators, the equality,

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inequality, less than, less than or equal,

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greater than, or greater
than or equal to operators.

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In this case, yes it's the same word,

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but one of them is spelled
with an uppercase letter

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and one with a lowercase
letter, so these are not equal.

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And of course, correspondingly,

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if I change that to a not equals operator,

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we will, in fact, get true.

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Now if I change that
operator to a less than sign

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because a capital O is
less than a lowercase o,

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this will be true, and so will, of course,

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less than or equal because
it's still less than

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in that case.

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If I change the operator
to a greater than sign,

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capital O is not greater than lowercase o

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in terms of as key values,

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so capital a is less than lowercase A,

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capital o will be less
than lowercase O as well.

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Therefore, this will result in false,

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as will the greater
than or equal operator.