The following article on router vs. switch vs. hub enumerates the difference between these three entities.
These three are computer networking devices, which are used to connect two or more computers across a single network, or across multiple networks. Each of them have their own set of individual properties and networking suitabilities.
The sections in this article highlight some of the essential differences between these devices. The concepts are fairly simple; you need not have a technical background to grasp what is depicted. You will however, get a clearer picture once you go through the points enlisted in the comparison charts below.
Switch Vs. Hub
Router Vs. Switch
I hope the above tables would have given you a good idea of the functionality of these three networking devices and their differences.