If you’re using SendGrid as an SMTP relay from another application, or using one of our APIs to programmatically send your email then you would fall into the Transactional Category. The content of the emails can be either transactional or marketing- you would be building the emails and managing your lists, using SendGrid as the Delivery Engine. The Marketing email tool allows you to upload and manage recipient lists, build template emails or your own HTML, and then schedule your campaigns through SendGrid.

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