It’s a growing collection of Integrated analytics, Computing, Database, Mobile, Networking, Storage, and Web services all supported by a network of Microsoft-Managed Datacentres, which helps you to move faster, achieve more and save money through various solutions

Infrastructure as a Service (IAAS )

Infrastructure as Service (IaaS) is one of the three fundamental service models of cloud computing alongside Platform as Service and Software as a Service (Saas).  All cloud computing services provides access to computing resource in a virtualised environment, “the Cloud”, across a public connection, usually the internet. In the case of IaaS the computing resource provided is specifically that of virtualised hardware, in other words, computing infrastructure. The definition includes such offerings as Virtual server space, Network connections, Bandwidth, IP addresses and Load balancers. Physically, the pool of hardware resource is pulled from a multitude of servers and networks usually distributed across numerous Data centers, all of which the cloud provider is responsible for maintaining. The client, on the other hand, is given access to the virtualised components in order to build their own IT platforms.
Scalability
SCALABILITY
Resource is available as and when the client needs it and therefore, there are no delays in expanding capacity or the wastage of unused capacity
No-investment-in-hardware
NO INVESTMENT IN HARDWARE
The underlying physical hardware that supports an IaaS service is set up and maintained by the cloud provider, saving the time and cost of doing so on the client side
Utility-style-costing
UTILITY STYLE COSTING
The service can be accessed on demand and client  pays for the resource that they actually use
Location-independence
LOCATION INDEPENDENCE
The service can usually be accessed from any location as long as there is an internet connection and the security protocol of the cloud allows it
Scalability
PHYSICAL SECURITY OF DATA
CENTRE LOCATIONS
Services available through a Public cloud, or Private cloud hosted externally with the cloud provider, benefit from the physical security afforded to the servers which are hosted within a Data centre
No-single-point-of-failure
NO SINGLE POINT OF FAILURE
If one server or network switch, for example, were to fail, the broader service would be unaffected due to the remaining multitude of hardware resources and redundancy configurations.  For many services if one entire data center were to go offline, never mind one server, the IaaS service could still run successfully

Platform as a Service (PAAS)

Software as a Services (SAAS)