You can create as many databases as you wish, limited only by disk space.
To Create A New Database
On the Main Menu choose "File/Create Database".
You will be presented with the standard Windows Save dialog. Navigate to the folder on the disk where you want to save the new database to and enter the name of the database in the filename input box.
After clicking on Save, your new database is created and is automatically opened ready for entering data.
Introduction to Database Files
Opening A Database File
Repairing and Optimizing Database Files