Work center and Routine

Dear All,

I am doing PP module course and i that i am not able to understand the use of work center and routine for Finsihed good.

Suppose i feed 100 units (Sodium chloride of 5kg pack) order in SAP then what is the role of work center and routine for this 100 units (Sodium chloride of 5kg pack).

Can any body explain me work center and routine in details and also provide me related T-code details for this ?

Share knowledges to become expert.............Thanks

Regards,

Phalgun patel