> For the complete documentation index, see [llms.txt](https://dev.ubidots.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://dev.ubidots.com/plugins/public-plugins/cron.md).
# Cron
## Definition
A public Cron plugin is Ubidots-defined logic that runs periodically at intervals set by the user.
## How to use Cron plugins
Go to Ubidots → Devices → Plugins. Select the Cron plugin you want to create an instance of and configure its parameters, including the execution period.
After you create the plugin, its logic runs at the defined frequency.
The following screenshot shows the creation modal for a Cron plugin. The red rectangle highlights the *run every* setting, which defines how often the logic runs:
## Available public Cron plugins
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## Querying This Documentation
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