Apache TinkerPop graph computing framework

Describe the Apache TinkerPop framework.

Apache TinkerPop™ is a graph abstraction layer that works with numerous different graph databases and graph processors. TinkerPop is composed of two elements: a structure API and a process API.

The primary components of the TinkerPop structure API are:
Graph
Maintains a set of vertices and edges.
Vertex
Extends a general class Element and maintains a set of incoming and outgoing edges as well as a collection of properties and a vertex type. DSE Graph schema stores VertexLabel - ID, name, Time-To-Live (TTL).
Edge
Extends Element and maintains an incoming and outgoing vertex as well as a collection of properties and an edge type. DSE Graph schema stores EdgeLabel - ID, name, TTL, multiplicity (multi, simple), unidirected, visible, sort-key.
Property
A string key associated with a value. DSE Graph schema stores PropertyKey - ID, name, TTL, datatype, cardinality (single, list).
VertexProperty
A string key associated with a value as well as a collection of metadata properties (vertices only).
The primary components of the TinkerPop process API are:
TraversalSource
A generator of traversals for a particular graph, domain specific language (DSL), and execution engine.
Traversal<S,E>
A functional data flow process transforming objects of type S into object of type E.
GraphTraversal
A traversal domain-specific language (DSL) that is oriented towards the semantics of the raw graph (i.e. vertices, edges, etc.).
GraphComputer
A system that processes the graph in parallel and potentially, distributed over a multi-machine cluster.
VertexProgram
Code executed at all vertices in a logically parallel manner with intercommunication via message passing.
MapReduce
Computations that analyzes all vertices in the graph in parallel and yields a single reduced result.

A key feature of TinkerPop is Gremlin, a graph traversal language and virtual machine. TinkerPop and Gremlin are to graph databases what JDBC and SQL are to relational databases. Gremlin variants are available for many languages: Java, Groovy, Python, and others.