Colocation is a term used to describe a certain type of IT Hosting service provided by telecommunication facilities and data centers to clients who own equipment and need to house it. There are different levels of Colocation – from colocation of a single standard desktop computer or rack server to rack enclosures (cabinets) used for colocation of multiple computing appliances.

The minimum services provided by the host facility (data center) to a client are: space, power feed, access to internet service, power and cooling. The facilities usually house IT equipment into rack cabinets (See “Server Cabinet”, “19-inch Rack” and “Tower Server Rack”), mount them into rack units, connect them to special types of power distribution units (PDU) and connect them to networking equipment (network switches) to provide them with Internet connectivity.

Cloud Hosting is a Internet hosting service delivered from a Cloud computing generation IT infrastructure. Cloud computing term generally refers to a systems which combine the computing resources of a number of machines in order to provide High Availability, ability to scale up and down the services and more flexibility to the users.

The term Cloud Hosting can be also associated with another one – Clustered hosting. Despite that as of May 2011 the term Cloud Hosting is pretty broad term which is not precisely defined yet, we can consider any hosting service as a “Cloud” if it is delivered from a fully-redundant, multi-server system, in which the resources are dynamically scalable and often virtualized.