Cloud computing, commonly referred to as “the cloud”, has been and continues to be amongst the fastest growing and most important computer technologies. IBM defines cloud computing as the delivery of ondemand computing resources - everything from applications to data centres - over the internet on a pay for use basis. Although the term “cloud” has been popularly used since the end of 2000’s, cloud computing services such as Yahoo Mail and the erstwhile Hotmail (now Outlook), to name but a few, have been around since the mid 1990’s.
Cloud computing services can be broadly classified into three categories:
- Software as a Service (SaaS)
SaaS refers to applications which are hosted in the cloud (as opposed to installed on a computer), which run on distant servers, owned and operated by third party providers. SaaS applications connect to the user’s computer via the internet usually through a web browser. With the proliferation of smart phones and tablets, cloud applications are optimised to run on these devices, either through a browser or a dedicated app. Gartner estimates US$99.5bn was spent on SaaS solutions in 2019, accounting for 44% of total cloud computing revenues of US$227.8bn in 2019. Major SaaS providers include Microsoft, Salesforce, Adobe, SAP, Oracle, Google and Workday amongst others.
- Infrastructure as a service (IaaS)
Infrastructure as a service provides companies with computing resources including servers, networking, storage, and data centre space on a pay-per-use basis. Gartner estimates IaaS spending increased 24% YoY to US$40.3bn in 2019. Amazon Web Services (AWS), Microsoft Azure, Google Cloud, Alibaba Cloud, IBM Cloud and Oracle Cloud are amongst some of the largest IaaS companies in the world. Major European IaaS providers include OVH Cloud, Deutsche Telekom and Orange Cloud.
- Platform as a Service (PaaS)
Platform as a service provides a platform to customers to develop, run and manage applications without the complexity of building and maintaining the infrastructure associated with developing and launching an application. The PaaS market size increased by 22% in 2019 to US$32.2bn, according to Gartner. Some of the largest PaaS companies include AWS, Azure, Google Anthos, IBM App Connect and Oracle Cloud.