Using cloud computing services, subscribers access online resources through workstations, laptops, tablets, and smartphones that are configured to protect the data and assets hosted on the cloud. With a pay-as-you-go model, cloud services offer a low-cost way to accommodate spikes in demand more efficiently than in-house computing services.

The power, flexibility, and agility of cloud services has led to a myriad of uses, with more being invented every day
Email: Perhaps the first cloud service ever offered, email doesn’t require any software to be installed on a local device to be able to use it. The application itself is hosted on the cloud—a SaaS use case.
Big Data Analytics: Big Data refers to the huge amounts of information that businesses such as Amazon and Facebook collect to understand human buying behavior. Now, most companies use their own customer data to make decisions on sales, marketing, R&D, and more. Using cloud services to store, manage, and analyze this data offers a powerful advantage—an IaaS use case.

Because of the cloud’s flexibility, users can build environments, test them, and tear them down quickly. What previously took months to provision can now take just a few minutes, which is a perfect scenario for highly iterative processes, such as software development. With PaaS, developers do not need to bother with maintenance, so they’re free to concentrate on development.

Using IaaS, you can access nearly unlimited storage space with built-in data lifecycle management policies. Using a deep data storage service, you can implement a data backup and archive process for any data that is over 30 days old. Just like that, as long as you have access to the Internet, you have access to the data no matter what happens to your facility.

Organizations often use IaaS for web hosting so they can balance the traffic load across multiple servers and scale up and down quickly and automatically as traffic fluctuates. The ability to provision and implement automatic scaling simplifies the whole process and takes out much of the administrative input and maintenance required.

Providers offer subscribers the use of their software running on a cloud infrastructure, which means the application can be widely distributed and accessed. Common types of business technologies hosted by the SaaS vendor include productivity suites, customer relationship management (CRM) software, human resources management (HRM) software, and data management software. Users have the option of accessing the application(s) through a program interface or a thin client interface, such as a web browser. With this service, subscribers are limited to access and use of the software only. The provider handles everything else: managing and controlling the network, servers, operating systems, storage, virtualization, data, middleware, and even individual application capabilities. SaaS apps are usually designed to be simple to use for a wider audience.

With PaaS, users have a bit more control than with SaaS because users gain access to a framework from the operating system up. PaaS allows users to place their own applications onto the cloud infrastructure with programming languages, libraries, services, and tools supported by the provider. The subscriber has control over the deployed applications, data, and possibly configuration settings for the application-hosting environment. But the network, servers, operating systems, and storage are managed and controlled by the provider.

Using IaaS, subscribers can architect an entire environment by configuring a virtual network that is segmented from other networks. Within this environment, users run an operating system and provision the processing, storage, networks, and other fundamental computing resources needed to run software on the cloud infrastructure. With IaaS, the subscriber may also have limited control of select networking components (e.g., host firewalls). Some providers will also offer services such as monitoring, automation, security, load balancing, and storage resiliency.

There are several other service models defined as XaaS, which do not strictly fit in the above three categories. They are essentially anything as a service and are often limited to narrower offerings. Disaster Recovery as a Service, Communications as a Service, and Monitoring as a Service are good examples.