# Polling

Polling is executing a periodic action checking for a state change. Examples are pinging a host, calling a REST API, or listing an Amazon S3 bucket for newly uploaded files.

Cadence support for long running activities and unlimited retries makes it a good fit.

Some real-world use cases:

  • Network, host and service monitoring
  • Processing files uploaded to FTP or S3
  • Polling an external API for a specific resource to become available