d924f03e_sselaer_Data_Warehouse_Project__data_warehousing_systems
[operational systems] Operational systems are generally process-oriented or process-driven, meaning that they are focused on specific business processes or tasks. Example tasks include billing, registration, etc. [data warehousing systems] 
Data warehousing systems are generally subject-oriented, organized around business areas that the organization needs information about. Such subject areas are usually populated with data from one or more operational systems. As an example, revenue may be a subject area of a data warehouse that incorporates data from operational systems that contain student tuition data, alumni gift data, financial aid data, etc.
Operational Systems vs. Data Warehousing - Rensselaer Data Warehouse Project
data warehousing systems