The SAP R/3 basis system is generally known as middleware or kernel, which is the nucleus of R/3 system. It is the set of programs and tools that interfaces with the operating system, the database, the network communication protocols, and the presentation interfaces. It is independent of operating system or database the R/3 system is installed on and guarantees the integration of all application modules.
A R/3 system is a client system.During each user session we can access only the data of the client selected during logon.A client,in organizational terms is an independent unit in R/3 system. Each client has its own data environment and hence its own master data and transaction data,assigned user master records, chart of accounts and specific customizing parameters.
For clients to logon to system a user master record relevant to the client must be created.To secure user access password security has been implemented. Passwords are hidden and we see asteriks when we type characters.For the language to be used for a logon session choose the language from Language input field.
Multiple log ons are logged in the system. This is for security purpose and license purpose. A warning message occurs if the same user tries to log on more than once.The multiple logon warning message offers three options:
1) Continue with the current logon and end any other logons in the system
2) Continue with the current logon without ending any other logons in the system
3) Terminate current logon
