using the schedule trigger event, you can run workflows on a recurruing schedule.

It uses Cron as the syntax to define at what time the workflow should be triggered and executed.

If you are unfamiliar with Cron, crontab guru is a great reference for Cron expressions, but at the core, it is 5 fields

┌───────────── minute (0 - 59)
│ ┌───────────── hour (0 - 23)
│ │ ┌───────────── day of the month (1 - 31)
│ │ │ ┌───────────── month (1 - 12 or JAN-DEC)
│ │ │ │ ┌───────────── day of the week (0 - 6 or SUN-SAT)
│ │ │ │ │
│ │ │ │ │
│ │ │ │ │
* * * * *

Example

Say you wish to run a workflow every hour on the hour (0:00, 1:00, 2:00, etc), then we can write the following YAML

name: Run task on the hour
on:
  schedule:
    - cron: 0 * * * *
jobs:
  # various jobs

or maybe we want to do the same, but not on the weekends

name: Run task on the hour (excluding weekends)
on:
  schedule:
    - cron: 0 * * * 1-5 # 1 is Monday, and go all the way till 5 or Friday.
jobs:
  # various jobs