Use Email-to-Case to automatically turn customer emails into cases, so your agents can quickly track and resolve their issues.
There are two versions of Email-to-Case:
On-Demand Email-to-Case, which uses Salesforce Apex email services
Email-to-Case, which uses an agent on your machine
Each version supports a different business case.
In this lesson, I walk you through those business use cases for Email-to-Case.
Send and Receive Emails with Email-to-Case - https://help.salesforce.com/articleView?err=1&id=customizesupport_email.htm&type=5