The F connector stands for an F-type connector, which is known as a coaxial cable connector used for television, cable TV, satellite TV, etc. And it is usually working with RG6 or RG59 cable.
The RJ45 connector, also called Registered Jack 45 connector, is a network interface used to connect computers to the Ethernet. It contains 8 pins and is usually compatible with twisted-pair cables for data transmission.
The BNC connector refers to Bayonet Neill–Concelman. It is a coaxial RF cable that is widely used to deliver signals of video, television, or other RF equipment.