1. Circuit switching: Here each user has a dedicated route and all his packets come via that route. So, it is very reliable and network congestion won't affect once connection is established. An example is telephone system. The below image showsa similar analogy for cars on road where each car is following a dedicated line (assume no line switching).
2. Packet Switching: This is the exact opposite where each packet can follow its own route and the header of the packet carries the route information. This is similar to cars in Bangalore city.
3. Message Switching: This is somewhere in between the two. A message is routed in a dedicated route (not all messages of a user). An example is email. In road we can consider a bridge where a car is forced to follow a lane.
