Account:  The entire customer entity.  An Account is comprised of a number of API Users (business units).

API:  An Application Program Interface (API) is self-service software that allows applications to communicate with each other, often without any user awareness or involvement.  An API makes it simpler to develop a program by providing all the materials for facilitating interactions between separate software programs.

API User:  A set of credentials to permit interaction with the API.  Typically there is one API User per Business Unit.

Attribute:  A property of a resource.  For example, First Name is a property of a Subscriber, while Encoding is a property of a Message Template.

Authentication:  A security method of identifying an individual based upon a username and an associated password.  Authentication guarantees that the individual is who he or she claims to be, but does not have the ability to set or determine the access rights of the individual.

Business Unit:  The level of organization within an Account which has its own collection of subscribers and message templates.  In Yesmail’s existing data model, Business Unit is equivalent to “Company”.

ETag:   Short for Entity Tag, is a value that identifies not only a unique instance of a resource, but also a specific version of that unique instance.  It's used by API platforms to detect conflicting attempts to update a resource. 

If-Match:  Only performs an action if the client-supplied ETag matches the same entity on the server.  It is primarily utilized for methods like PUT to only update a resource if it has not been modified since the user last updated it.

JSON:  Abbreviation for JavaScript Object Notation, it is a text-based open standard data-interchange, based on a subset of JavaScript syntax. It is useful when writing any kind of JavaScript-based application, including extensions. The Enterprise APIs currently processes only JSON formatted payloads.

Message:  The output result from triggering a send operation on a Message Template.  This refers to the actual email, SMS or social media posting that was sent.

Message Template: See Template.

Message Targeting:  See Targeting.

Parameter:  A special kind of variable used in a computing science subroutine to refer to one of the pieces of data provided as input to the subroutine.  These pieces of data are called arguments. An ordered list of parameters is usually included in the definition of a subroutine, so that, each time the subroutine is called, its arguments for that call can be assigned to the corresponding parameters.

Payload:  Refers to either the information passed to a resource within an HTTP request (as parameter/value pairs, or as a JSON object), or the information returned from that request.  An Input Payload is the sender side message payload.  An Output Payload is the receiver side message payload.

Subscriber:  An individual targeting unit, as defined by the Account.  The term Subscriber is used regardless of subscription status; a Subscriber may be unsubscribed from all messages.

Subscriber ID:  An identifier code, provided by the Account, that uniquely specifies a particular Subscriber.  

Subscriber List:  A named list of subscribers and their attributes, to be added or updated to the Subscribers database, or to be included within the Message Targeting.

Target:  The collection of Subscribers to which a particular Message was sent, as calculated at runtime.

Targeting (Message Targeting):  The collection of Subscriber Attribute information used to determine the Message recipient list.  The Message Targeting may consist of one or more Personas, one or more combinations of subscriber attributes, and/or one or more explicitly defined lists of Subscribers. Note that the Message Targeting is dynamic, while the Message Target is frozen and represents the collection of Subscribers meeting the Targeting criteria at a specified point in time.

Template (or Message Template):  The collection of information about an individual event to be triggered to a particular marketing Channel.

Trigger:  An event that results in a message being sent.

Unsubscribe:  When an email recipient requests to no longer receive email communication from a particular sender. The option to unsubscribe from a mailing list is required by law to be available on all email marketing communications.

URI:  Short for Uniform Resource Identifier, the generic term for all types of names and addresses that refer to objects on the World Wide Web.  For example, a URL is one type of URI.

User:  An individual employee of an Account who interacts with the API.