Although the current version of the Oracle object-relational database is Oracle9i, there are many Oracle9i products from which to choose. Fortunately, as a web developer, you'll most likely interact with only these products:
Oracle Server/Standard Edition
Oracle Enterprise Edition
Oracle Personal Edition
Oracle positions the Oracle Server/Standard Edition as an entry-level database for a small number of users. Typically, when someone refers to Oracle8i or Oracle9i, they mean the Standard or Enterprise Edition. This product is available today for Windows NT, NetWare, and Unix platforms and for HP/UX, IBM AIX, Linux, and Sun Solaris.
Oracle Enterprise Edition is targeted to large-scale deployments of database applications to serve a multitude of users. As such, Oracle Enterprise Edition offers scalability and reliability in both single- and multisystem configurations running on platforms ranging from Windows to most flavors of Unix. Enterprise Edition provides the most complete feature set of all the Oracle product family, including features focusing on database extensibility, performance, and management.
Oracle Personal Edition is the single-user version of Oracle Enterprise Edition. Since the feature set matches that of the Enterprise Edition, Personal Edition is perfect for development or for learning Oracle. Using Personal Edition, you can write applications and later promote the application to the Standard or Enterprise editions.
Oracle9i Lite, targeted toward mobile computing, enables the delivery of web applications to a broad range of mobile devices. Oracle9i Lite is an add-on to the Oracle9i Application Server. Lite supports development for Windows, Palm Computing, EPOC, and different flavors of Windows CE such as Pocket PC and HPC-Pro.