Split horizon prevents routers from advertising a route through the same interface from which the route was learned. Thus split horizon prevents routing loops, not
switching loops. By default, split horizon is enabled on all interfaces except those on which Frame Relay encapsulation or Switched Multimegabit Data Service (SMDS)
encapsulation is enabled. In addition, Routing Information Protocol (RIP), which is a distance-vector protocol, uses split horizon. To enable split horizon, you should issue
the ip split-horizon command from interface configuration mode. To disable split horizon, you should issue the no ip split-horizon command from interface
configuration mode.

Poison reverse prevents routing loops by advertising a route as unreachable to the interface from which the route was received. Split horizon is similar to poison reverse
in that both methods prevent routing loops. However, poison reverse advertises a route as unreachable to the source interface, whereas split horizon does not.

Hold-down timers also prevent routing loops. Hold-down timers suppress information regarding a better path to a route for a specified period Of time. When a router
receives a routing update stating that a route is unreachable, the router waits a specified amount of time before accepting routes advertised by other sources.

Spanning Tree Protocol (STP) prevents switching loops on a network. Switching loops can occur when there is more than one switched path to a destination. The  spanning tree algorithm determines the best path through a switched network, and any ports that create redundant paths are blocked. If the best path becomes unavailable, the network topology is recalculated and the port connected to the next best path is unblocked.