# What are 'logics' in Slicer

**URL:** <https://discourse.slicer.org/t/what-are-logics-in-slicer/23679>\
**Category:** Support\
**Created:** [June 1, 2022, 9:55pm UTC](https://discourse.slicer.org/t/what-are-logics-in-slicer/23679 "2022-06-01T21:55:56Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![gzt036](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/gzt036/32/15418_2.png) [@gzt036](https://discourse.slicer.org/u/gzt036)\
**Post date:** [June 1, 2022, 9:55pm UTC](https://discourse.slicer.org/t/what-are-logics-in-slicer/23679/1 "2022-06-01T21:55:56Z")

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I am new to Slicer and I am confused with the class names, could someone help to explain what is ‘loadable’, what is ‘logics’ in plain language? I mean, what is the idea using ‘Logics’ as class name?

Thanks!

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**Author:** ![jamesobutler](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/jamesobutler/32/7511_2.png) [@jamesobutler](https://discourse.slicer.org/u/jamesobutler)\
**Post date:** [June 1, 2022, 10:05pm UTC](https://discourse.slicer.org/t/what-are-logics-in-slicer/23679/2 "2022-06-01T22:05:24Z")

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PerkLab has a Slicer bootcamp that has materials that could be helpful for you. Download the [day3\_2\_SlicerProgramming](https://github.com/PerkLab/PerkLabBootcamp/raw/master/Doc/day3_2_SlicerProgramming.pptx) powerpoint.

The “loadable” part is likely referring to the fact that the these modules are “loaded” whenever Slicer is started. Modifying these modules would require restarting Slicer to re-load the modules. The various module types are explained in more detail in the linked PerkLab powerpoint.

“Logic” is referring to everything that is not user interface related. It is the internal processing for a module. More is explain in the linked PerkLab powerpoint.