How devices are connected to the network through the actual cables that transmit data, or the physical structure of the network, is called the physical topology.
Logical topologies are bound to network protocols and describe how data is moved across the network.
Internet topology refers to the logical topology of the internet. There are attempts to study internet topology by network scientists such as Albert-László Barabási. There are also attempts by networks of individuals to deliberately manipulate internet topology, which could be referred to as virtual terraforming. Cases and possibilities include a distributed denial-of-service attack (DdoS), in which virtual smart mobs flood a site with hits/links, or correspondingly, cease all traffic/remove all links to a site; the strategic use of linkback and reverse-linking to change the connectedness and therefore searchability of sites; and incorporating the long tail into search engines, e.g. with an option to search for poorly linked sites. Internet topology may change dramatically as internet architecture moves from a conception of links that is binary (yes/no link) or spectral (strength of link) to one that is typological (type of link). For example, as Facebook moves from a binary conception of relationship (yes/no friend) to a typological one (type of relationship) with its “How do you know [insert name]?” feature, the topology of its social network will change; specifically, its social network will become social graphs. If something similar were applied to links between sites on the internet, it would drastically terraform what Albert-László Barabási identifies as the 4 continents of internet topology.