What is cloud computing ?
In the simplest terms, cloud computing means storing and accessing data and programs over the Internet instead of your computer's hard drive. The cloud is just a metaphor for the Internet. Although cloud computing has changed over time, it has been divided into three broad service categories: infrastructure as a service (IaaS), platform as a service (PaaS) and software as a service (SaaS).The cloud is also not about having a dedicated network attached storage (NAS) hardware or server in residence. Storing data on a home or office network does not count as utilizing the cloud. When you store data on or run programs from the hard drive, that's called local storage and computing. For it to be considered "cloud computing," you need to access your data or your programs over the Internet. At the very least, have that data synced with other information over the Web. In a big business, you may know all there is to know about what's on the other side of the connection. As an individual user, you may never have any idea what kind of massive data processing is happening on the other end. The end result is the same: with an online connection, cloud computing can be done anywhere, anytime.
Cloud-based apps can be up and running in days or weeks, and they cost less. With a cloud app, you just open a browser, log in, customize the app, and start using it.
Businesses are running all kinds of apps in the cloud, like customer relationship management (CRM), HR, accounting, and much more. Some of the world’s largest companies moved their applications to the cloud with Salesforce after rigorously testing the security and reliability of our infrastructure.
As cloud computing grows in popularity, thousands of companies are simply rebranding their non-cloud products and services as “cloud computing.”
A cloud can be private or public. The public cloud lets customers gain new capabilities without investing in new hardware or software. Instead, they pay their cloud provider a subscription fee or pay for only the resources they use .Popular public cloud offerings—such as Amazon Web Services (AWS), Salesforce’s CRM system, and Microsoft Azure—all exemplify this familiar notion of cloud computing.
Private cloud services are delivered from a business's data center to internal users. This model offers the versatility and convenience of the cloud, while preserving the management, control and security common to local data centers. Internal users may or may not be billed for services through IT chargeback. Common private cloud technologies and vendors include VMware and OpenStack.
Private or public, the goal of cloud computing is to provide easy, scalable access to computing resources and IT services.
Cloud computing definitions for each type
The array of available cloud computing services is vast, but most fall into one of the following categories.
Infrastructure as a Service (IaaS)
A third party hosts elements of infrastructure, such as hardware, software, servers, and storage, also providing backup, security, and maintenance.
Software as a Service (SaaS)
This type of public cloud computing delivers applications over the internet through the browser. The most popular SaaS applications for business can be found in Google’s G Suite and Microsoft’s Office 365.
Platform as a Service (PaaS)
FaaS, the cloud version of serverless computing, adds another layer of abstraction to PaaS, so that developers are completely insulated from everything in the stack below their code.
· Everyone is talking about “the cloud.” But what does it mean?, 2018, https://www.salesforce.com/what-is-cloud-computing/
· What is cloud computing ?, https://azure.microsoft.com/en-in/overview/what-is-cloud-computing/
· What is cloud computing? Everything you need to know about the cloud, explained, December 13, 2018, https://www.zdnet.com/article/what-is-cloud-computing-everything-you-need-to-know-from-public-and-private-cloud-to-software-as-a/