The change of word form according to grammatical function, which occurs in inflected languages.

Inflection is differentiated depending on the class:

There are two basic types of inflection: Linguistically, the former is strictly called agglutination, and the latter is the true sense of the word inflection. However, in the popular imagination, agglutination is discarded and the umbrella term inflection used.

Words often do not appear in a fundamental form (the word root) except in dictionaries and grammars.

A schema of all inflections for a word is sometimes called a paradigm.

Various major languages, including English, German, Russian, Spanish, French, and Hindi - all Indo-European languages - are inflected to a greater or lesser extent.

The most obvious inflections in English occur in strong verbs, e.g. I am, you are and to take, I took; and nouns, one man, all men; foot, feet. Weak inflections, however, are more common, such as I love, I loved, he loves; John, John's car.