What is the difference between ArcGIS online and Arcgis portal?

Check out the below Esri documentation to understand the relationship and difference between ArcGIS Online and Portal for ArcGIS. https://enterprise.arcgis.com/en/portal/10.5/administer/linux/choosing-between-an-arcgis-online-subscription-and-portal-for-arcgis.htm

The provided text is a reference to ESRI documentation that discusses the decision-making process between using an ArcGIS Online subscription and Portal for ArcGIS. The link directs to a specific page that likely contains detailed information on the differences, benefits, and considerations for choosing between these two options.