# What is "1 hot \*"

**URL:** <https://community.deeplearning.ai/t/what-is-1-hot/176645>\
**Category:** Unsupervised Learning, Recommenders, Reinforcement\
**Tags:** week-module-2\
**Created:** [August 2, 2022, 11:33pm UTC](https://community.deeplearning.ai/t/what-is-1-hot/176645 "2022-08-02T23:33:40Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Pierre\_BEJIAN](https://sea1.discourse-cdn.com/dlai/user_avatar/community.deeplearning.ai/pierre_bejian/32/23252_2.png) [@Pierre\_BEJIAN](https://community.deeplearning.ai/u/Pierre_BEJIAN)\
**Post date:** [August 2, 2022, 11:33pm UTC](https://community.deeplearning.ai/t/what-is-1-hot/176645/1 "2022-08-02T23:33:40Z")

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Hi,  
Sorry to ask such a basic question but I have come across the notion of “1 hot someting” several times in the specialization. I don’t understand at all what this is about.  
Here is an example:

 ![hot](https://global.discourse-cdn.com/dlai/original/3X/a/1/a1940d5efccba8c6d8e76bac5213430da0a201e6.jpeg)

Thanks for your help  
Regards  
Pierre

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**Author:** ![rmwkwok](https://sea1.discourse-cdn.com/dlai/user_avatar/community.deeplearning.ai/rmwkwok/32/126977_2.png) [@rmwkwok](https://community.deeplearning.ai/u/rmwkwok)\
**Post date:** [August 3, 2022, 12:49am UTC](https://community.deeplearning.ai/t/what-is-1-hot/176645/2 "2022-08-03T00:49:38Z")

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Hi @Pierre_BEJIAN , we use one-hot encoding to encode a categorical variable into multiple binary variables. For “Gender”, it can include “male”, “female”, “transgender”, “gender neutral” and more, so when you encode this variable, for each category value it forms a binary variable such as “is\_male”, “is\_female”, “is\_transgender”, “is\_gender\_neutral” and so on. Each of the binary variable can take a value of 0 or 1.

Raymond