Initial pseudostate - points to the initial State of an Object Instance - An instance is a concrete manifestation of an abstraction to which a set of operations can be applied and which has a state that stores the effect of the operation. Interaction diagram Interaction overview diagram Interaction Frame - a section of a Sequence diagram, divided into fragments, which is subject to an algorithmic Operator such as iteration, parallelism or optionality. Interface - a defined communication boundary. J Join - a point in an activity diagram where several concurrent flows (threads) synchronize, waiting until all are complete before continuing with a single flow L Lifeline - indicates a participating Object or Part in a sequence diagram. The Lifeline may show activation, Object creation, and Object deletion. Link - a relationship between objects. While an Object is an instantiation of a Class a Link can be seen as an instantiation of an Association. M Merge - a point in an activity diagram marking the end of the optional behavior started by a Decision Message - a signal from one object (or similar entity) to another, often with parameters. Often implemented as a call to a Method, including the Constructor and Destructor, of an Object in a Sequence diagram. Metadata - Metamodel - Metamodeling - Metamodeling technique - Meta-Object Facility - Method - Modeling - Domain - the representation of real world conceptual entities Design - the representation of software Classes and Interfaces Dynamic - use of Interaction diagrams to describe collaborations and behavior model - Model-driven architecture (MDA) - Multiplicity - 1. A specification of the number of possible occurrences of a property, or the number of allowable elements that may participate in a given relationship. In UML 1.x, it was also possible to have a discrete list of values, but this was eliminated in UML 2.0. 2. It specifies how many objects may be connected across an instance of an association which is written as a range of values (like 1..*). Mandatory - A required multiplicity, the lower bound is at least one, usually 1..1 or 1 Optional - The lower bound is at most zero, usually, 0..1 Many - A multiplicity with no upper limit, either 0..* or * Forbidden - No elements allowed, 0..0 (in UML 2.2) N Namespace - a context in which an identifier exists. Navigable - the ability for objects of a Class