Explain Hub, Switch and Router in detail?

 Hub

 A hub is a networking device that allows multiple devices to connect to it and communicate with each other. When a device sends data to a hub, the hub broadcasts the data to all the other devices connected to it. This means that all the devices connected to the hub receive the data, even if it was intended for just one device. Hubs are simple and inexpensive, but they have several limitations. One of the main limitations is that they do not have the intelligence to direct data to specific devices, so they can cause network congestion if there are a large number of devices connected to them.

Switch

 A switch is a networking device that is similar to a hub, but it has more intelligence. When a device sends data to a switch, the switch looks at the destination address of the data and forwards it to the specific device it was intended for. This allows the switch to direct data to specific devices, which can improve network performance and reduce congestion. Switches can also create multiple virtual networks (called VLANs) on a single physical device, which can be useful for creating isolated networks.

Router

 A router is a networking device that is used to connect multiple networks together. When a device sends data to a router, the router looks at the destination address of the data and forwards it to the appropriate network. Routers use routing tables to determine where to send the data, and they can be configured to send data over the most efficient path. In addition to connecting networks, routers also have the ability to perform network address translation (NAT), which allows multiple devices on a network to share a single public IP address. Routers also have built-in security features, such as firewalls, that can help protect the network from external threats.