1. What is visualforce controller in salesforce? What are they? Visualforce controller is a set of instructions that specify what happens, when user interacts with components on visualforce pages, such buttons & links. Here are the 3 types of controller 1. Standard Controller, 2. Custom controller & 3. Controller extensions. 2. What is Standard Controller? Standard controller provides the salesforce in built functionality to interact with visualforce pages. You can use the standard actions like Save, Edit, Cancel & delete by using standard controllers. Syntax : <apex:page standardController=”Account”> 3. What is Custom Controller? Custom controller is an apex class that implements customized logic to visualfore pages. We can override or create new functionality by using custom controllers. Syntax: <apex:page controller=”Account” > 4. What is Standard List Controller? Standard List Controller allow...