Normally called, I believe, “Incremental forever”, but it’s possible some backup vendor calls it the other way.

At some point, you make a full backup of your system, say over the weekend when business is slower. Then each evening during the week, you’d make an incremental backup. The Monday night incremental would be the changes since that last full backup completed. The Tuesday night incremental would be just the changes since the Monday night incremental. Wednesday since the Tuesday, etc., until you got to Friday or Saturday night, when you’d do another full backup.