The Email field is commonly used and can have widespread impact across the rest of your program. You will want to use this field if you A) want to ensure that applicants type in a valid email address, and B) you want to send emails to these addresses at a later date.
To add an Email field to the submission form, click Email on the left side panel of the form builder.
Available Field Settings
The only special field setting for an Email field is the confirmation setting. By checking this box, it will simply require the applicant to type the email address in a second time and make sure that the emails match in both fields (to ensure that the applicant did not mistype it). This is rarely used though.
An important usage of the Email field is that you can send emails to these addresses at other points in OpenWater. For example, on a successful submission by the nominator, you may want to send an email to the nominee informing them that someone else has nominated them for this program. This can be done by configuring your confirmation emails and clicking Insert Variable in the Override To field.