Lost in all the technical jargon? Find definitions for common email and technical terms and learn more with our related resources.


An Application Programming Interface (API) is a programmatic way for applications to communicate with one another. An email API is a specific type of API that allows email developers to integrate their applications with email service providers (ESPs). This lets email developers send and receive emails and take advantage of ESPs’ email analytics and deliverability services from within their own environments.

Abandoned cart email

An abandoned cart email is a triggered (or transactional) email sent to customers when they leave a web shop without purchasing the items in their shopping cart. It acts as a friendly reminder to encourage potential customers to take action, converting them to buyers after they have navigated away from your site.


An allowlist, formerly known as a whitelist, is a list of approved senders or recipients that are permitted to send emails to a particular inbox. It is used to ensure that emails from known and trusted sources are allowed to pass through a filter.


The “Archives” folder is listed in an email client alongside other standard folders like the inbox and spam folders. The folder is where users can store old messages, reports, and letters. In email marketing, archiving is the process of moving emails from an inbox to a specific Archives folder. It’s important to periodically archive emails as it declutters the inbox.

Authentication protocols

An authentication protocol is a cryptographic standard that validates the sender and receiver. It acts as an ID card to verify a brand’s identity to both email servers and inbox service providers (ISPs), ensuring the brand is credible.

Automated emails

Automated emails are email messages automatically sent by a CRM or software, usually triggered by a user’s actions. These emails are also called transactional emails.

Automation flow

Automation flow is a practice of mechanizing tasks like responding to customer inquiries, creating sales invoices, and testing new products. This allows brands to free up their employees’ time to focus on high-value tasks like developing marketing strategies and communicating with customers.


An autoresponder is a feature that automatically responds to incoming emails. Users generally rely on an autoresponder when they’re out of office or dealing with a large volume of emails. Brands use an autoresponder to send emails confirming certain user actions, like placing an order or receiving a payment.