Opening/Closing System

Hi Guys,

In some cases, we open the SAP system to do some configuration for certain tables.

We have to request the Basis team to open the SAP system..What exactly do we mean by this opening of the system?

Are we allowing the customization of certain tables which is otherwise not possible in the Quality system?

And we again need to close the system..What is the purpose of this opening/closing....

thanks

srik.