This article gives a brief description and advantages and disadvantages of the three major network topologies: bus, star, and ring.
Connects each node in a line - cable runs from one PC to the next and from there to the next, etc.
Actually there are two variations of the Bus topology:
The Bus topology's disadvantage is that a break in the backbone takes down the entire network, although the malfunctioning of a single node does not affect the network as long as the integrity of the cable is maintained.
Connects all nodes to a centralized hub. Most popular topology for Ethernet.
If all of a hub's ports are in use then it can simply be connected to another hub.
Although the Ring looks a lot like the Star because each node is connected to a central device, the two work very differently.
Packets are (attached to a token and) sent around the ring and examined by each node.
Difficult to maintain because just one down node breaks the chain.