When you send a emails to multiple people at once using the same email content, you’re sending a campaign. Anytime you send emails in MergeMail, you’re sending a campaign.
In MergeMail, you can use a Google Sheet to collect multiple recipients for your campaign. Add an “Email” column to your Google Sheet, and MergeMail will automatically detect that column and use those emails as the recipients in your campaign.
To see how to create a campaign, see Quick Start.