Visualforce is not only a powerful way to create entirely new pages for your application but also augments the Salesforce user interface in multiple places. As we've seen so far, you can use it to extend the standard UI layouts and Custom Buttons. Here is a list of platform areas that accept Visualforce pages:
Layout sections
Custom Buttons
Custom Tabs
Custom Tab Splash page
Chatter Custom Publisher Actions
Sidebar component
Dashboard component
Force.com sites
Profiles and Permission Sets also reference Visualforce pages; users must be given access to a page before they can use it from these areas.
While Salesforce provides many components to use within the Visualforce pages, the only component that is strictly required is the apex:page component. That's it!
<apex:page>Anything I like in here!</apex:page>
When studying the attributes of the apex:page component, it's clear that this is a powerful way to communicate with the browser, returning...