[1] Examples include but are not limited to road networks, railways, air routes, pipelines, aqueducts, and power lines.
[2] In the 1970s, the connection was reestablished by the early developers of geographic information systems, who employed it in the topological data structures of polygons (which is not of relevance here), and the analysis of transport networks.
Early works, such as Tinkler (1977), focused mainly on simple schematic networks, likely due to the lack of significant volumes of linear data and the computational complexity of many of the algorithms.
[3] The full implementation of network analysis algorithms in GIS software did not appear until the 1990s,[4][5] but rather advanced tools are generally available today.
[6] The core of a network dataset is a vector layer of polylines representing the paths of travel, either precise geographic routes or schematic diagrams, known as edges.
The most popular method of solving this task, implemented in most GIS and mapping software, is Dijkstra's algorithm.
[13] For example, the preferred service area for a fire station would be the set of street segments it can reach in a small amount of time.