What is Cloud Computing?

What should you do if you're asked a question on IT and not sure...say Cloud Computing, the term is used so often within IT but what actually is it? It is described in similar ways by different sources below:

The definition of cloud computing I use is "a collection of computing services and resources which is hosted over the internet being consumed when it is needed typically on a pay-as-you-go price." This allows for a flexible and efficient IT model to be created for a business.

Different Types of Cloud Computing

Public Cloud

• Anyone can utilise this platform, such as SMEs to large enterprises.
• The Cloud Service Provider (CSP) owns a data centre and rents out rack space to different clients which is then accessed over the Internet.
• Management responsibilities are given to the CSP.
• The clients don't have control over the location of the servers.
• Examples: Microsoft Azure, AWS, Google Cloud Platform, Alibaba, Rackspace.

Private Cloud

• This infrastructure is used for one single organisation, also known as the internal cloud.
• The infrastructure can be hosted at the business being on-premise or hosted in a data centre belonging to a third-party.
• It will be managed and maintained by either the organisation/third-party/both.
• A firewall is created by the IT department to protect the infrastructure and maintained on a private network, meaning it's more secure.
• Examples: Hewlett Packard Enterprise Private Cloud Services.

Hybrid Cloud

• Combination of public and private clouds, creating a intermediary.
• Uses one or more of each cloud with physical or virtualised servers.
• Mixes both efficiency with security, privacy and control.
• Hybrid approach can be used for businesses to slowly move their data to the cloud due to reasons like uncertainty, skill and time.
• Well known for its flexibility and scalability.

Each cloud type can be run with different Cloud Services; IaaS, SaaS and Paas.

IaaS: Infrastructure as a service. You hire IT infrastructure - servers and VMs, switches, storage, systems, networks - from a CSP on a pay-as-you-go pricing. 

SaaS: Software as a service. You access software applications over the internet. CSP's host and manage the application along with the underlying infrastructure, handling maintenance.

PaaS: Platform as a service. An environment for creating, testing, delivering and managing software applications with no hassle of managing the underlying infrastructure.

I've written this article as in the IT industry everyday you hear the term Cloud Computing being mentioned. This was designed to explain the different types of Cloud and different Services available.