# 21.10: String Comparison

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The relational operators work on strings. To see if two strings are equal:

if word == 'banana':
print 'All right, bananas.'


Other relational operations are useful for putting words in alphabetical order:

if word < 'banana':
print 'Your word,' + word + ', comes before banana.'
elif word > 'banana':
print 'Your word,' + word + ', comes after banana.'
else:
print 'All right, bananas.'


Python does not handle uppercase and lowercase letters the same way that people do. All the uppercase letters come before all the lowercase letters, so:

Your word, Pineapple, comes before banana.


A common way to address this problem is to convert strings to a standard format, such as all lowercase, before performing the comparison. Keep that in mind in case you have to defend yourself against a man armed with a Pineapple.

This page titled 21.10: String Comparison is shared under a CC BY-NC-SA 3.0 license and was authored, remixed, and/or curated by Allen B. Downey (Green Tea Press) .