Understanding URL Syntax

Each application has a number (called an application ID) that uniquely identifies it. Similarly, each page also has a unique number (called a page ID). Applications and pages may also have alphanumeric aliases. Application aliases are unique within a a database user account and page aliases are unique within each application. When you run an application, the Application Express engine generates a session number that serves as a key to the user's session state.

Topics:

Understanding the URL that Displays for a Page
Using f?p Syntax to Link Pages
Calling a Page Using an Application and Page Alias
Calling a Page from a Button URL