Cloud computing service is served through the internet or dedicated network. The service is delivered on demand and you have to pay according to your usage. The range of Cloud Computing includes full applications and development platforms, servers, storage, and virtual desktops.
In a traditional IT environment, software and hardware are funded up front by department and implemented over a period of months. But in cloud computing, services are delivered to any IT resources in minutes to hours and manages costs to actual usage. So, organizations have better agility and can align expenses more efficiently than the traditional one.
Cloud computing services work by maintaining virtualization, multi-tenancy, network-access, on demand, elastic metering/chargeback. The most common cloud computing services are; Software as a Service (SaaS), Infrastructure as a Service (IaaS) and Platform as a Service (PaaS).