Why to form an auto answer of mail?

What is an auto answer of Post office?

An auto answer can send a predefined answer to any mail that you receive.

Why it would use this?

For example, if you go away of vacation you can automatically let know to your clients who you are not available to answer its post office.

Does the auto answer interfere with the delivery of e-mail messages?

No, the e-mails of your clients continue being in your inbox.