SAS software automatically defines two permanent libraries, Sashelp and Sasuser, at the beginning of each SAS session. (Depending on the SAS software components that you have installed, SAS software may also define other libraries automatically.)

• Sashelp contains SAS files that control various aspects of your SAS session. The defaults stored in this library are for everyone using SAS software at your installation.
  
  
• Sasuser contains SAS files that enable you to tailor features of SAS software for your needs. Your personal settings are stored in the Sasuser library.
  
  Sasuser is also a convenient place to store files that you create for your personal use. For example, the data used in SAS OnlineTutor practices are stored in your Sasuser library.