Stemming and lemmatization

Text documents can contain words in different forms, such as play, playing, and played. They are similar and they have a common root.

Stemming and lemmatization are techniques that are used to find these common roots. Finding the roots will help us count, play, playing, and played as a single entity as all the words talk about play.

Stemming is more of a crude form of arriving at the root of a word; so, in the case of the preceding example, playing would be reduced to play. Lemmatization brings into context words, such as worse and bad, that can have a common bad root.


Stemming is a process of reducing a word to its root form. The root form is not a word by itself, but words can be formed by adding the right suffix ...

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