Introductory Guide to Cloud Computing
Our Cloud guide provides a comprehensive overview for understanding Cloud computing and how best to apply it to improve your business.

Our Cloud guide provides a comprehensive overview for understanding Cloud computing and how best to apply it to improve your business.
This introduction explains the different types of Cloud service options, and how to select the right one for your particular requirements.
Cloud service layers
Cloud Computing is defined to be made up of three main layers of service: IaaS, PaaS and SaaS.
While this is initially quite confusing jargon, it’s actually a helpful guide to understanding what type of service is right for your business needs, especially so when combined with a simple mapping to who would use each one.
Plesk provides such a guide:
This highlights the Cloud ‘stack’, how one layer builds upon the lower service and in total makes up Cloud computing, with each layer being intended for different, increasingly less technical types of users:
- IaaS – For system administrators who previously would have installed and built servers in their own local data centres. Now instead they can provision virtual servers in the global data centres of AWS or Microsoft.
- PaaS – For the software developers who would then use those servers, to write business applications. PaaS provides them automation tools and services to streamline and speed their development workflows.
- SaaS – Those business applications, provided online via a utility model (eg. priced per user). Previously they would have had to wait for the servers and applications to be installed and configured by technical staff, now they can set up them instantly themselves.
Another consideration is the “Pizza as a Service” analogy.
This compares the increasing scope of outsourced supplier services, how much management responsibility the provider owns versus what the customer manages, to how much work you do in the preparation of the pizza dinner.
This explains the scope of roles and responsibilities through an analogy ranging from ‘made at home’ right through full ‘dining out’.
So in the simplest of scenario exploration, small businesses are unlikely to be users of IaaS or PaaS, these are for larger organizations who have in-house teams of Sysadmins and Developers. AWS and Azure offer them powerful services at those layers that can greatly improve how they write and deliver software, and they want more control over this underlying technology.
In contrast small businesses typically don’t have those resources, so SaaS applications are ideal, as they require zero technical expertise to set up and use, and critically offer per user per monthly pricing options – They also don’t care how it is managed under the hood.
However for these same reasons SaaS is also equally useful to large enterprises. For example a marketing department who quickly needs a particular digital campaigning tool may not have the time to go through their internal processes and definitely not the months it would take to have developers create it from scratch. Again the primary value of SaaS is the quick, frictionless set up.
Cloud Service Selection
So fundamentally the decision of selecting the right Cloud service for your organization is a process of these different levels of user comparing the available options to their preferences and needs.
AWS and Azure have varying IaaS features that will matter to Sysadmins, Developers have particular tools and ways of working that PaaS caters for in different ways, and business end users will have certain functionality they are seeking that can be compared to possible SaaS options.
As we reach the SaaS layer we find there are hundreds if not thousands of possible SaaS solutions available today, for any and all desired use case scenarios. FinancesOnline provides this very helpful list of just some of these, highlighting how these can be categorized by industry and functional features, from Accounting through HR, e-commerce and restaurant management among many others.