From time to time, you may want to backup your data from ArcGIS Online to your local machine. This can be done for archiving purposes or as a preventative measure. This link provides instructions on How to back up content in ArcGIS Online. Here are some things to be aware of when backing up your organizations content:
- Best practice is to save individual copies of your data to a local machine
- Be aware that any content deleted from your organization is permanently removed and cannot be recovered
- Data types such as shape files, map and layer packages, FDGB, CSV, Excel, GeoJSON, and KML files can be downloaded
- For hosted features service items and layers, use the Export Data/Download content method
So thats a quick recap of backing up data in ArcGIS Online. Please read the support link on backing up data for step by step instructions and more detail for the methods as described.