What is the Cloud?


The course is part of this learning path

What is The Cloud?

This module explains what servers and data centers are, before explaining what the cloud is and contrasting the different types of cloud service models. 

Learning Objectives 

The objectives of this Course are to provide you with and understanding of: 

  • the basic components and operation of servers and data centers. 
  • what the cloud means and its role in providing software, hardware and other computer services. 
  • the different types of cloud service models. 
  • the key business benefits of cloud services, including economic and security benefits. 

Intended Audience 

The Course is aimed at anybody who needs a basic understanding of what the cloud is, how it works, and the important considerations for using it. 


Although not essential, before you complete this Course it would be helpful if you have a basic understanding of server hardware components and what a data center is.  


We welcome all feedback and suggestions - please contact us at to let us know what you think. 


Too embarrassed to ask what the cloud is and how it works? Why is it called the cloud anyway? Does it exist up in the sky in the ether? Is there just one cloud or are there lots of them? Well, stay tuned. This video is intended to clear the skies and bring a ray of sunshine to your day. Okay, that was a bit cheesy. Whether we know it or not, we are almost likely using the cloud in one way or another. Every time you open your Gmail account, watch a show on Netflix, or check your Instagram, you are using the cloud. Before the cloud existed, you might have saved files, pictures, and videos to your hard drive, and used a computer-based application to read your emails. In the workplace, all of this was traditionally managed by the company server. These days, however, data and applications can be stored and accessed in the cloud. Cloud computing has become so commonplace that an estimated 83% of the workforce now resides in the cloud, and that number is increasing.

Okay, so what exactly is the cloud? You may be surprised to find out that the cloud isn't up in the sky at all. It is very much on terra firma. When data is stored in the cloud, it is actually stored on a server somewhere, and you access it via the internet. Cloud servers are located in data centers all over the world, often called server farms.

And why is it called the cloud? The phrase, the cloud, was first used as slang. When the internet was in its early stages, technical diagrams often used a cloud symbol to represent the servers and networking infrastructure that made up the internet. When computing processes began moving to the servers and infrastructure part of the internet, people used the phrase, moving to the cloud, as a way of describing the process. The term stuck, and nowadays the cloud is the term we use to describe this type of computing.

Cloud computing relies on a technology called virtualization where digital-only virtual computers operate independently inside a physical computer. The technical term is a virtual machine. The beauty of virtual machines is that they are very lightweight, so one physical machine can host many virtual machines. One server becomes many servers, and one data center becomes many data centers. You get the picture, it's economical. If an individual server goes down, this generally doesn't affect the performance of the cloud server, making the system very reliable. Users can connect to the cloud from any device over the internet and can access files and services either through an app or through their browser.

Let's look at an example. Say you lose your mobile or it breaks. On it, you have all of your emails, Instagram and Facebook posts and all of your photos. If you weren't using cloud technology, all of this data would be lost along with the phone. But with cloud computing, you know that when you open your accounts on a new or different device, it will still all be in place, with all of your photos, videos, and conversation history saved. There are many other benefits to using the cloud. Individuals and companies don't have to manage physical hard drives or servers themselves or run software applications on their own machines. In many cases, you can access your data offline, edit and update files, and then sync it later when you have an internet connection. Colleagues can even collaborate on the same document in real time. Because the remote servers handle most of the computing and storage, you don't necessarily need an expensive high-end machine to get your work done, and data is backed up in multiple locations through a process called redundancy, which means your data won't be lost.

For businesses, switching to cloud computing gets rid of IT costs and overhead. You no longer need to update and maintain your own server. The cloud can make it easier for you to operate internationally, and employees, contractors, and customers can all access the same files and applications from any location.

Of course, there are some drawbacks to operating in the cloud. Without an internet connection, you can lose access to your data and applications indefinitely. The same applies if there are any technical issues or outages on the server side. Also, because your information is stored online, there is always the risk of cyber attack. Cloud services will have security measures in place so it is generally not an issue, but it's always a good idea to be cautious about what you store in the cloud.

The forecast for cloud computing is bright. As more and more businesses adopt this technology, it is becoming part of our everyday virtual lives, making our digital experiences more flexible, efficient, and economical.


DHCP and DNS - Firewall - Encryption - Hubs, Switches and Routers - The 7 Layers of the OSI Model and Encapsulation - Unicast, Multicast and Broadcast


About the Author

Daniel Ives has worked in the IT industry since leaving university in 1992, holding roles including support, analysis, development, project management and training.  He has worked predominantly with Windows and uses a variety of programming languages and databases.

Daniel has been training full-time since 2001 and with QA since the beginning of 2006.

Daniel has been involved in the creation of numerous courses, the tailoring of courses and the design and delivery of graduate training programs for companies in the logistics, finance and public sectors.

Previous major projects with QA include Visual Studio pre-release events around Europe on behalf of Microsoft, providing input and advice to Microsoft at the beta stage of development of several of their .NET courses.

In industry, Daniel was involved in the manufacturing and logistics areas. He built a computer simulation of a £20million manufacturing plant during construction to assist in equipment purchasing decisions and chaired a performance measurement and enhancement project which resulted in a 2% improvement in delivery performance (on time and in full).

Covered Topics