Learning Apex

After you have your developer account, there are many resources available to you for learning about Apex
Apex Trailhead Content
Beginning and intermediate programmers
Several Trailhead modules provide tutorials on learning Apex. Using these modules you’ll learn the fundamentals of Apex and how you can use it on the Lightning Platform to add custom business logic through triggers, unit tests, asynchronous Apex, REST Web services, and Visualforce controllers.
Quick Start: Apex
Apex Basics & Database
Apex Triggers
Apex Integration Services
Apex Testing
Asynchronous Apex
Salesforce Developers Apex Page
Beginning and advanced programmers
The Apex page on Salesforce Developers has links to several resources including articles about the Apex programming language. These resources provide a quick introduction to Apex and include best practices for Apex development.
Lightning Platform Cookbook
Beginning and advanced programmers
This collaborative site provides many recipes for using the Web services API, developing Apex code, and creating Visualforce pages. The Lightning Platform Cookbook helps developers become familiar with common Lightning Platform programming techniques and best practices. You can read and comment on existing recipes, or submit your own recipes, at http://developer.force.com/cookbook.
Development Life Cycle: Enterprise Development on the Lightning Platform
Architects and advanced programmers
The Application Lifecycle and Development Models module on Trailhead helps you learn how to use the application lifecycle and development models on the Lightning Platform.
Training Courses
Training classes are also available from Salesforce Training & Certification. You can find a complete list of courses at the Training & Certification site.
In This Book (Apex Developer's Guide)
Beginning programmers should look at the following:
In addition to the above, advanced programmers should look at: