WP-CLI makes many routine WordPress tasks automatic and easier, including updating the core software, plugins, themes. The command line interface also enhances the process of backing up WordPress databases, managing user roles and much more. A full list of commands are available on the project site and a list of community commands is posted to GitHub.
Siteground is one of a few list of hosts that offer WP-CLI Pre-Installed
SiteGround offers a tutorial to help customer master WP-CLI. The tutorial explains how to use the WP command line interface in order to complete tasks such as upgrades, WP database backups, plugin and themes installs and deletions, publishing and deleting posts, changing a WordPress site URL settings, etc.