As Drupal module maintainers, we at Nextide need to be constantly updating our modules to add new features or patch issues.  Whether your module is available for download or is a custom module for a client site, you can't expect users to uninstall and reinstall it to pick up new features.  If you have data or configuration changes, update hooks are mandatory to learn.  This post will show how we created a new content entity in a Drupal update hook.