A company that purchases SAP software will install it on its servers, and then configured
to the company’s specific needs. This is called an instance. Companies can
have more than one SAP instance, but the instances will exist on different SAP
systems. A number of clients will be created within one SAP instance. A client is
an organizational and legal entity in the SAP system. The master data is protected
within the client because it cannot be accessed from outside. The master data in a
client is only visible within that client and cannot be displayed or changed from
another client. There will be multiple clients in an SAP system. Each of these clients
can have a different objective, and each client represents a unique environment.
A client has its own set of tables and user data. Objects can be either client
dependent or client independent. SAP objects that are used by only one client are
client dependent. Objects that are used by all of the clients in an SAP system, such
as ABAP/4 programs, are client independent.