Once you have a Developer Edition or sandbox organization, you may want to learn some of the core concepts of Apex. After reviewing the basics, you are ready to write your first Apex program—a very simple class, trigger, and unit test.
Because Apex is very similar to Java, you may recognize much of the functionality.
This tutorial is based on a custom object called Book that is created in the first step. This custom object is updated through a trigger.
This Hello World sample requires custom objects. You can either create these on your own, or download the objects and Apex code as an unmanaged package from the Salesforce AppExchange. To obtain the sample assets in your org, install the Apex Tutorials Package. This package also contains sample code and objects for the Shipping Invoice example.