Cloud Computing

What Does Cloud Computing Mean?

Cloud computing is a service model that allows information technology (IT) customers to obtain computing resources over the internet. In network diagrams and flowcharts, an icon that resembles a cloud is traditionally used to represent the internet.


A cloud computing environment has five important characteristics that differentiate it from a traditional computing environment:

  • Self Service – the customer can provision computing resources by themselves, on demand.
  • Network Access – resources are provisioned and accessed over the internet.
  • Resource Pools – resources are pooled together to serve the needs of multiple customers.
  • Elasticity – resources can be rapidly provisioned or scaled down depending on real-time need.
  • Measured Services – resource usage can be monitored and controlled by the customer.

Cloud Deployment Models

Organizations have several choices for deploying a cloud computing models:

  • Public Clouds – allow resources to be accessed by authorized subscribers.
  • Private Clouds – restrict resource access to a specific group or organization.
  • Community Clouds – allow resources to be shared among two or more organizations.
  • Hybrid Clouds – resources are provided by at least two cloud service providers.

Cloud Delivery Models

Organizations have several choices for delivering cloud computing:

Software as a Service (SaaS) – SaaS is the form of cloud service that most consumers are familiar with. When SaaS applications are used in business, it tends to reduce the cost of software ownership by removing the need for technical staff to install, manage and maintain software. SaaS applications can be free or purchased through a subscription model. Tier 1 SaaS vendors include Google, Salesforce and Microsoft.

Platform as a Service (PaaS) – The provider manages backend resources for software, including operating systems, middleware and databases. PaaS services are used to improve developer productivity and reduce time-to-market. Tier 1 vendors include Microsoft Azure, Amazon Web Services, Google Cloud, IBM Cloud and Oracle Cloud Infrastructure.

Infrastructure as a Service (IaaS) – IaaS allows customers to virtually build a data center without having to invest in capacity planning or the physical maintenance and management of it. Tier 1 vendors include AWS Elastic Compute Cloud , Google Compute Engine and Alibaba Elastic Compute Service.

Techopedia Explains Cloud Computing

The adoption of cloud computing offers multiple benefits, but also presents challenges that must be considered when evaluating and deciding when to use a cloud service.

Some consider cloud computing an overused buzzword that has been blown out of proportion by marketing departments. A common argument from critics is that cloud computing cannot succeed because it means that organizations must lose control of their data. A large regulated company, like a bank, might be required to store data in the United States. While this is not an insurmountable issue, it demonstrates the type of data sovereignty issues that some companies are having with cloud computing.

History of Cloud Computing

The concepts behind cloud computing are not new. As early as 1960, researchers proposed the idea that computing would become a utility service like water, telecom or electricity.

Around the same time, IBM helped develop strategies for logically segmenting their mainframe computers so they could serve multiple clients within the same organization. Each client viewed mainframe resources as if they were the sole user when in reality, they were sharing resources with other users.

By the late 1980s, organizations began to understand that instead of buying or leasing an expensive Big Iron mainframe, they could purchase a number of relatively inexpensive personal computers (PCs) and network them together so they functioned like one machine. The idea of using the internet to connect multiple distributed computing sytems so they could work together on a single problem is the foundation of cloud computing.

Milestones for using cloud computing in business include:

1999 – Salesforce introduced the idea of delivering enterprise software over the internet.

2006 – Amazon launched Amazon Web Services and the per-per-use business model.

2008 – Google launched their App Engine as a Platform as a Service (PaaS).

2009 – Alibaba builds its first data center.

2010 – Microsoft released Microsoft Azure.

2010 – Rackspace Hosting and NASA launched OpenStack.

2012 – Oracle announced Oracle Cloud.

2012 – HP announced HP Converged Cloud

2013 – VMware announced vCloud Hybrid Services

2022 – Research firm Gartner predicts cloud spending to reach $500 billion by the end of the year. SaaS remains the largest public cloud services market segment.


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Margaret Rouse

Margaret Rouse is an award-winning technical writer and teacher known for her ability to explain complex technical subjects to a non-technical, business audience. Over the past twenty years her explanations have appeared on TechTarget websites and she's been cited as an authority in articles by the New York Times, Time Magazine, USA Today, ZDNet, PC Magazine and Discovery Magazine.Margaret's idea of a fun day is helping IT and business professionals learn to speak each other’s highly specialized languages. If you have a suggestion for a new definition or how to improve a technical explanation, please email Margaret or contact her…