SAP users can be created using transaction code SU01. While creatingSAP users there are only 2 mandatory fields User name on the Addresstab and Initial Password field on the Logon Data tab page. All otherentries on this screen are optional. But if proper roles are not assignedto the user, then the user won’t be having authorization to open anytransaction code. Users and authorization data are client-dependent.Main tasks that can be performed using transaction code SU01 are
1)Creating a User
2)Copy an Existing user to a new user
3)Modifying a User
4)Deleting a User
5)Lock/Unlock a User
6)Modifying a User’s Password
7)Add a Role to a User
There are five types of users in sap
Dialog users (Type A)These type of users are used for Individual and interactive system access.Dialog users can log into the system using interface called SAPGUI(Newer versions of GUI can be downloaded from SAP Marketplace).During first logon, the user has to change the initial password.Also multiple logons are possible with SAPGUI (default value is 6).Multiple logons can be restricted using the parameter login/disable_multile_gui_login.
System Users (Type B)System users are used for Background processing and communicationwithin a system (such as RFC users for ALE, Workflow, TMS, and CUA).Dialog logon is not possible for these type of users.
Communication Users (C)Dialog-free communication for external RFC calls.Service Users (S)Dialog user available to a larger, anonymous group of users.The system does not check for expired/initial passwords during logon.Only the user administrator can change the passwords.
Reference Users (L)General, non-person related users that allows the assignment ofadditional identical authorizations, such as for Internet userscreated with transaction SU01. No logon is possible.