One of the greatest reasons for the success of the internet is the adherence to various protocols. Just like in your home where you plug an electrical device into an electical outlet and expect it to work, the same applies to computer components. It is because the electrical device adheres to established electrical specifications that this is able to happen.

The OSI model  (Open Systems Interconnection) is an abstract description for layered communications and network design. It is made up of seven layers.

• Physical layer – the basic hardware transmission technologies of a network. It is the fundamental layer underlying the logical data structures of the higher level functions in a network.
• Data Link Layer –  provides the functional and procedural means to transfer data between network entities.
• Network Layer – responsible for end-to-end packet delivery, including routing through intermediate hosts.
• Transport Layer –  establishes a direct, virtual host-to-host communications transport medium for applications and therefore also referred to as transport protocols
• Session Layer – provides the mechanism for opening, closing and managing a semi permanent dialogue between end-user application processes.
• Presentation Layer – responsible for the delivery and formatting of information to the application layer for further processing or display
• Application Layer – used in categorizing protocols and methods in architectural models of computer networking.