To use networks for a purpose, whether it be for empowering its members, building an audience for something, or to bring about change, its useful to understand how networks work. There are several network structures, such as hub and spoke, star-shaped, and scale-free networks, and each might require a different strategy for forming connections and spreading information. Different types of networks also have different functions, and understanding these functions can help one determine how to use them to achieve one's ends. The Overseas Development Institute (ODI) is a thinktank on international development and humanitarian issues. One of its projects is the study of how to use networks to bridge research and public policy. The following articles are taken from from the Networks: Bridging Research and Policy project page of the ODI website, maintained by Enrique Mendizabal.

 
Supra functions - What Networks Exist For

The supra function of a network is defined by how members use it to achieve their ends:

Agency
The Agency network is used as the main agent of what its members want to achieve. The network is coordinated, and members contribute to its work, and expect the network to take the lead in bringing about the desired end.

Support
The Support network provides its members with the resources they need to achieve their goals. Members contribute back to the network, but do not expect the network to achieve anything for them.

Functions - What Networks Do

This article builds on the work of Richard Portes and Stephen Yeo in describing 6 functions networks can play. Not all networks provide all 6 functions, and some can only provide a few depending on the goal of their design.

Filter
A filtering network takes a large amount of information from many sources and only lets the information worth paying attention to through. For example, policy makers have a network of advisers that only pass on the information necessary to make decisions.

Amplify
An amplifying network makes private, complex information public and simple, disseminating it widely outward from its source. It can also provide a two way communication channel, with information traveling back from many nodes to a single one.

Invest/Provide
Investing networks provide channels for resources needed to carry out member's main activities. These resources are supplied internally or from sources outside of the network, with the network acting as facilitator by making the necessary connections between supply and demand

Convene
Convening networks bring different people and groups together. Convening networks require tools to reach out to very specific audiences

Build Communities
Community Building networks promote and sustain shared values and standards among members. They build strong internal connections, but can also suffer from weak external links, and therefore may be less effective for having an impact outside of the network.

Facilitate
Facilitating networks enable members to work more efficiently and effectively through actions that support the work without being part of the work itself, such as mentoring and professional development activities.