There are two options to store your content data of your applications on your Microsoft SharePoint environment.
This option stores the files uploaded to the site as binary content in content database tables. With this option active, default settings of SharePoint recycle bin will be in use when deleting content. These settings — described in details below — keeps the deleted content in content database and enables you to restore it even after 60 days (default value is 30 + 30 days).
RBS (Remote Blob Storage)
Remote Blob Storage is a whole other subject and we will focus on some of the problems we face on this subject. To learn more about RBS, I recommend reading this article: https://docs.microsoft.com/en-us/sharepoint/administration/rbs-overview
If I have to briefly explain, it is about storing binary BLOB data which is stored in content database by default outside of content database. In the case where RBS is used, default recycle bin in SharePoint works the same way, however in addition to the default setting of 30 + 30 days, garbage collection process of RBS must be performed. Otherwise, deleted SharePoint content will continue to take up space on the disk.