https://developer.salesforce.com/signup - Sign up for Developer Edition org
https://developer.salesforce.com/page/An_Introduction_to_Apex - printed
https://developer.salesforce.com/page/An_Introduction_to_Visualforce - printed
https://developer.salesforce.com/page/An_Introduction_to_Force_Database - printed
Apex - need to clean up
Data Types - need to to enrich and print
Apex Trigger - need to clean up
Monitoring Asychronous Jobs
Integration & Callouts
Lightning App Builder
trust.salesforce.com - live performance data, planned maintenance, security, and more.
The power of record types: One object holds many similar but different records.
Remove buttons from Listview in Visualforce page.