# DSE Graph Terminology

Explain terminology specific to DSE Graph.

This terminology is specific to DSE Graph.
A collection of unordered lists used to represent a finite graph. Each list describes the set of neighbors of a vertex in the graph.
A vertex directly attached to another vertex by an edge.
directed graph
A set of vertices and a set of arcs (ordered pairs of vertices). In DSE Graph, the terminology "arcs" is not used, and edges are directional.
edge
A connection between vertices. Edges can be unordered (no directional orientation) or ordered (directional). An edge can also be described as an object that has a vertex at its tail and head.
element
An element is a vertex, edge, or property.
global index
An index structure over the entire graph.
graph
A collection of vertices and edges.
graph degree
The largest vertex degree of the graph.
graph partitioning
A process that consists of dividing a graph into components, such that the components are of about the same size and there are few connections between the components.
graph traversal
An algorithmic walk across the elements of a graph according to the referential structure explicit within the graph data structure.
incident edge
An edge incident to a particular vertex, meaning that the edge and vertex touch.
index
An index is a data structure that allows for the fast retrieval of elements by a particular key-value pair.
meta-property
A property that describes some attribute of another property.
order
The magnitude of the number of edges to the number of vertices.
partitioned vertex
Used for vertices that have a very large number of edges, a partitioned vertex consists of a portion of a vertex's data that results from dividing the vertex into smaller components for graph database storage. Experimental
property
A key-value pair that describes some attribute of either a vertex or an edge. Property key is used to describe the key in the key-value pair. All properties are global in DSE Graph, meaning that a property can be used for any vertices. For example, "name" can be used for all vertices in a graph.
traversal source
A domain specific language (DSL) that specifies the traversal methods used by a traversal.
undirected graph
A set of vertices and a set of edges (unordered pairs of vertices).
vertex-centric index
A local index structure built per vertex.
vertex
A vertex is the fundamental unit of which graphs are formed. A vertex can also be described as an object that has incoming and outgoing edges.
vertex degree
The number of edges incident to a vertex.