I'm sure you've all received out-of-office / automatic replies to your emails - you send an email to someone and instantly an email comes back telling you they're out of the office until XX.
These messages help manage expectations when you're not around to respond to messages promptly and they can also give alternative contact details or a link to a FAQ page where answers to common questions can be found.
We live in a time when instant access to people and information is expected but it puts a lot of pressure onto a business owner and their team to always be available to everyone and in the end, to give quality service, you can't be instantly available at all times or you never get a chance to do whatever the job is you're supposed to be doing.
To allow yourself some time and space, particularly if you're out of the office for a meeting/event or on holiday, it's good to decide before hand how often you are going to check your email or if someone else will be dealing with enquiries/support during that time. When you know what the plan is, you simply need to tell everyone else and an automatic response to an email is just the thing. Here's a quick video to show you how to set up an Out Of Office response in Outlook and Gmail.