This document uses the following terms:
atom feed: An XML structure that contains metadata about content, such as the language version and the date when the content was last modified, and is sent to subscribers by using the Atom Publishing Protocol (AtomPub), as described in [RFC4287].
Attachment object: A set of properties that represents a file, Message object, or structured storage that is attached to a Message object and is visible through the attachments table for a Message object.
Coordinated Universal Time (UTC): A high-precision atomic time standard that approximately tracks Universal Time (UT). It is the basis for legal, civil time all over the Earth. Time zones around the world are expressed as positive and negative offsets from UTC. In this role, it is also referred to as Zulu time (Z) and Greenwich Mean Time (GMT). In these specifications, all references to UTC refer to the time at UTC-0 (or GMT).
Message object: A set of properties that represents an email message, appointment, contact, or other type of personal-information-management object. In addition to its own properties, a Message object contains recipient properties that represent the addressees to which it is addressed, and an attachments table that represents any files and other Message objects that are attached to it.
Really Simple Syndication (RSS): An XML-based syndication format for content, as described in [RSS2.0].
remote operation (ROP): An operation that is invoked against a server. Each ROP represents an action, such as delete, send, or query. A ROP is contained in a ROP buffer for transmission over the wire.
Uniform Resource Locator (URL): A string of characters in a standardized format that identifies a document or resource on the World Wide Web. The format is as specified in [RFC1738].
XML: The Extensible Markup Language, as described in [XML1.0].
XML element: An XML structure that typically consists of a start tag, an end tag, and the information between those tags. Elements can have attributes and can contain other elements.
MAY, SHOULD, MUST, SHOULD NOT, MUST NOT: These terms (in all caps) are used as defined in [RFC2119]. All statements of optional behavior use either MAY, SHOULD, or SHOULD NOT.