As mentioned in the introduction to this documentation, tags work to merge dynamic information about an appointment or a client into the email that is sent out. There are several tags that are already on your email templates and available for you to use (see full list here). One of the most commonly used is the %APPT_DATE_TIME% which merges the date and time of the appointment to the email template. Let's take a deeper look at how this works.
First, let's navigate to the template list for the New Appointment by Client email template by going to Messaging > Appointment Templates and clicking the "View" button next to that category:
In the template list view, we can see that even the subject line for the default New Appointment by Client email uses the tag %APPT_DATE_TIME%:
If we click the view button next to the template listed here to go into that template's profile, we'll see that the tag is also used in the body of the email:
Obviously everyone who books appointments with you is not going to have the same date and time for their appointment. Jane Doe's appointment with you may be for Monday, December 12th, 2016 at 9:00am whereas John Doe's appointment might be Tuesday, December 13th, 2016 at 1:00pm. With information that changes like this, you can't hard code in a date and time.
By using tags, TimeTap is able to generate the date and time on the fly for the appointment. The %APPT_DATE_TIME% tag will be filled in when the appointment is generated (after the client books) with the date and time that they booked for.
Now the %APPT_DATE_TIME% tag will always be filled in for appointment based emails, but there are instances where you may not have any information to merge with the email template. Take, for instance, the %LOCATION_ADDRESS% field in the template from the screenshot above. It's not required that you put in an address for your location, so what would happen if you had left that field blank and this template generated?
In this case, the field would simply not fill in and would display as a blank space on your email template. You'll see on the screenshot below that on this test account I'm using for this documentation, when the email template was created, the business name filled in but nothing underneath it in the location address field:
This is because on this test account, I don't have an address entered for the location, thus the tag just disappears from the email template when it's generated.