A nerve consists of a bundle of nerve fibres. This bundle is called fasciculi.
A nerve is surrounded by epineurium, a layer of connective tissue.
A fasciculus is covered by perineurium which is connective tissue.
Inside the nerve, each nerve fibre is surrounded by endoneurium.
A nerve conveys information in the form of electrochemical impulses (known as nerve impulses or action potentials) carried by the individual neurons that make up the nerve.
These impulses are extremely fast, with some myelinated neurons conducting at speeds up to 120 m/s.
The impulses travel from one neuron to another by crossing a synapse, and the message is converted from electrical to chemical and then back to electrical.