Delivery Class defines how database table is going to be transported during installation, upgrade, and copies within landscapes, clients and customer systems.
Application table for master data and transaction data. Data is maintain by application. These tables are delivered to customer as empty tables.
Customer table used for customize application. Data is maintained by customer.
Table used as a repository to store temporary data. These tables are delivered to customer as empty tables.
Customer table where SAP can add data but not modify or delete it.
System table in which customers can make entries. System tables are delivered with some data (not empty).
System table delivered by SAP with predefined data as part of system.
System table for system administration data. A system table in the delivery class W usually delivered with predefined data by SAP and can be affected by customer modifications.
It’s defined while creating a new database table. Once we entered the new table name, we are redirected to the “Delivery and Maintenance” tab to define it.
You can find more information about this topic directly in SAP help.