Backups are automatically-created disk images of Droplets. Enabling backups for Droplets enables system-level backups at weekly intervals, which provides a way to revert to an older state or create new Droplets.
The DigitalOcean API lets you manage DigitalOcean resources programmatically using conventional HTTP requests. All the functionality available in the DigitalOcean Control Panel is also available through the API.
See the API documentation on backups for Droplets for more information.
doctl is a command-line interface for the DigitalOcean API and supports many of the same actions.
doctl documentation on Droplets for more information.