Oxford University Press's
Academic Insights for the Thinking World

Defining a network

The scientific study of networks is an interdisciplinary field that combines ideas from mathematics, physics, biology, computer science, statistics, the social sciences, and many other areas. It is a relatively understudied area of science, but its multidisciplinary nature means that an increasing amount of scientists are engaging with it.

A network is, in its simplest form, a collection of points joined together in pairs by lines. A point is referred to as a node or vertex and a line is referred to as an edge. Many systems of interest in the physical, biological, and social sciences can be thought of as networks, and there are four principle types of network:

  • 1. Technological networks are the physical infrastructure networks that form the backbone of modern technological societies. Perhaps the most celebrated such network—and a relatively recent entry in the field—is the Internet, the global network of data connections that links computers and other information systems together.
  • 2. Networks of information are networks consisting of items of data linked together in some way. Information networks are all, so far as we know, man-made, with perhaps the best known example being the World Wide Web, though many others exist and are worthy of study, particularly citation networks of various kinds.
  • 3. In the scientific study of networks, the phrase “social networks” has a much broader meaning: a social network is any network in which the nodes represent people and the edges represent some form of connection between them, such as friendship.
  • 4. Networks appear in many branches of biology as a convenient way of representing patterns of interaction between biological elements. Biological networks include metabolic networks, neural networks, and food webs.

These networks are simplified representations that reduce systems to an abstract structure or topology, capturing only the basics of connection patterns and little else. This makes the abstract study of its content and structure much clearer. The study of network structures is crucial, as understanding something about the structure of networks is essential to understanding fully how the corresponding systems work. Networks capture the pattern of interactions between the parts of a system, and these can have a large effect on the behaviour of a system.

See below for examples of each of the four types of network: from natural gas pipelines to 15th century Italian marriage ties.

Featured image credit: Connection by TheDigitalArtist. CC0 via Pixabay.

Recent Comments

  1. jay zhang

    where can i find the solution?

Comments are closed.