> ## Documentation Index
> Fetch the complete documentation index at: https://docs-classic.cognigy.com/llms.txt
> Use this file to discover all available pages before exploring further.

# User-Defined Slots

*User-Defined Slots* are custom Slots based on your vocabularies or regular expressions, allowing detection of specific phrases, entities, or domain-specific terms.

In Cognigy, you can create the following user-defined Slots:

* [Lexicon Slots](https://docs-classic.cognigy.com/ai/platform-features/nlu/slots/user-defined/lexicon.md) — specific words or phrases (and their variations) from a custom word list.
* [Regex Slots](https://docs-classic.cognigy.com/ai/platform-features/nlu/slots/user-defined/regex.md) — structured patterns, like phone numbers or emails, using regular expressions.


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