Link layer is the first lowest layer of the TCP/IP reference model, which describes how data should be physically generated and transmitted over the physical medium by the network devices.
The physical layer and data link layer of OSI reference model is combined together to form a link layer.
Following are the functions and responsibilities of link layer :
At physical level
At logical level
Protocols used: Ethernet, Token ring, X.25, Frame relay, FDDI, GPRS.
Network Devices: Network adaptor, Modem, Hub, Switch.
Beaware of phishing or fake sites like www.facebook.com as www.fackbook.com or anything like that. They are intended to get the login information of the user.