Database software such as SAS works differently than spreadsheets in that data is entered in individual records, and the records can then be presented in tabular format if the user so chooses. For example, in a database of client information, an individual record is created for each client with name, address and other pertinent information. The database can be used to print mailing labels for all clients, identify clients by specific characteristics -- such as, for example, all clients east of the Mississippi -- or present client information in tabular format.
An active worksheet is the worksheet that is currently open. For example, in the picture above, the sheet tabs at the bottom of the window show "Sheet1", "Sheet2", and "Sheet3", with Sheet1 being the active worksheet. The active tab usually has a white background behind the tab name.