Marketing email
One-to-many email sent on the senders schedule.
Marketing email is broadcast or behavior-triggered email used for promotion, lifecycle nurturing, or newsletters. Engagement metrics drive sender reputation more than for transactional, and recipient consent (CAN-SPAM, GDPR) is non-negotiable.
reading this as early-stage startups
At an early stage the deciding factors are what the free tier actually covers, what the first paid invoice looks like, and how much of a founding engineer's week the setup costs. Feature depth that only matters at a million sends a month is noise until it is not.
Applied to marketing email, that means weighing free tier, best published rate per 1,000, entry price, and developer experience ahead of the rest, against a waitlist, a launch announcement, onboarding email, and the first transactional sends.