The document discusses different types of computer network topologies. It defines network topology as the arrangement of elements in a communication network, which can be physical or logical. The main topologies described are bus, ring, star, and mesh. Bus topology uses a single cable to connect all nodes. Ring topology connects each computer to the two neighbors, forming a ring. Star topology has a central hub that connects all other nodes. Mesh topology connects computers via redundant links, with either full or partial connectivity between nodes.