Writing Apex | Apex Developer Guide | Salesforce Developers

Data Types and Variables
Apex uses data types, variables, and related language constructs such as enums, constants, expressions, operators, and assignment statements.

Control Flow Statements
Apex provides if-else statements, switch statements, and loops to control the flow of code execution. Statements are generally executed line by line, in the order they appear. With control flow statements, you can make Apex code execute based on a certain condition, or have a block of code execute repeatedly.

Working with Data in Apex
You can add and interact with data in the Lightning Platform persistence layer. The sObject data type is the main data type that holds data objects. You’ll use Data Manipulation Language (DML) to work with data, and use query languages to retrieve data, such as the (), among other things.