Substitution
From Wikipedia, the free encyclopedia.

In general, substitution is the replacement of one thing with another. There are many specific examples:

• In organic chemistry, a reaction where one functional group takes the place of another. A major type of substitution is nucleophilic substitution.

• The substitution cipher in cryptography.

• The substitution rule in calculus.

• Import substitution in trade.

• The substitution method in the testing of optical fiber.

• The substitution property of equality in mathematics.

This is a disambiguation page; that is, one that just points to other pages that might otherwise have the same name.

The original article can be found at: http://en.wikipedia.org/wiki/Substitution.
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