The business world is full of buzzwords but none seem to be gaining more traction in recent times than "cloud computing". But what exactly is cloud computing? There seem to be so many different definitions of what it entails that pinning down an exact definition is extremely difficult. In this article, we'll help demystify the concept of cloud computing by looking at how it is implemented in practical situations: what types of cloud services are being offered and who is using them? We'll also discuss how cloud computing is in many ways, an extension of the mainframe terminals of the 1970s, as well as the role that 3270 emulation and other emulators still play today.

Essentially, cloud computing refers to internet-based management and provision of data and applications. You're not storing anything on your own computer; you're storing it on the internet, or "in the cloud". Well, actually, you're storing it on remote servers controlled by the service provider, but you're accessing it via the internet. For these reasons and more, there are several advantages and disadvantages of cloud computing. They are as follows:


  • Access to data anywhere, any time
  • Less demand on your personal computer
  • Regular backing up of data by cloud service providers
  • No costly hardware upgrades


  • Security risk from hackers
  • Lower reliability
  • No access if internet isn't working
  • All data can be accessed by cloud service provider

In practical use, cloud computing is often employed through what is commonly referred to as Software as a Service (SaaS). This refers to business applications including but not limited to accounts management, content management, customer relationship management (CRM), enterprise resource planning (ERP), human resource management (HRM), and invoice management. SaaS models are usually accessed by users through a web browser, which connected to the centrally-hosted data via a "thin client" interface.

Personal Cloud Computing

Cloud computing services are not limited to business purposes, however. They are also commonly utilized for personal use. Take, for example, Apple's iCloud, which allows users to store data on computer servers that are owned by Apple. The iCloud helps Apple users synchronize data between their iPods, iPhones, iPads, iMacs and MacBooks.

Another commonly used cloud computing service is Google Docs, which is fast gaining popularity as an alternative to Microsoft Office as a viable office suite. Whereas Microsoft Office -- which includes established programs such as Word, Excel and Power Point -- requires documents to be saved to the user's hard drive, Google Docs offers the same functionality but allows users to save files to the internet. Whereas transferring Office files around involves saving them onto a portable hard drive or emailing them, Google Docs files can be accessed anywhere in the world; all that's needed is an internet connection and the appropriate access.

What's New is Old

Many people have pointed out that cloud computing is not as new a concept as some would have you think; in many ways, it's a return to the hardware terminals of the 1970s that were used to access mainframes. Just like with cloud computing, data and applications were stored on a central host -- the mainframe -- and accessed remotely via terminals. These days, mainframes can still be accessed with Windows terminal emulation software designed to complement the multi-function capabilities of modern PCs.

One of the biggest problems with traditional mainframes has always been their scalability, but with the advent of cloud computing and its ability to access host servers from anywhere in the world -- provided the user has password access and an internet connection -- this problem has a solution.