topology

The spatial relationships between connecting or adjacent coverage features (e.g., arcs, nodes, polygons, and points). For example, the topology of an arc includes its from- and to-nodes, and its left and right polygons. Topological relationships are built from simple elements into complex elements: points (simplest elements), arcs (sets of connected points), areas (sets of connected arcs), and routes (sets of sections, which are arcs or portions of arcs). Redundant data (coordinates) are eliminated because an arc may represent a linear feature, part of the boundary of an area feature, or both. Topology is useful in GIS because many spatial modeling operations don't require coordinates, only topological information. For example, to find an optimal path between two points requires a list of the arcs that connect to each other and the cost to traverse each arc in each direction. Coordinates are only needed for drawing the path after it is calculated.

The spatial relationships between connecting or adjacent coverage features.

The geometric arrangement of a computer system. Common topologies include a bus (network topology in which nodes are connected to a single cable with terminators at each end), star (local area network designed in the shape of a star, where all end points are connected to one central switching device, or hub), and ring (network topology in which nodes are connected in a closed loop; no terminators are required because there are no unconnected ends). Star networks are easier to manage than ring topology.

The physical, non-logical features of a card. A card may have either standard or enhanced topography.

See network topology.