Cloud Computing is comprised of two words: one is Cloud which means ‘the internet’ and the other one is Computing which simply implies ‘world of computation’, so Cloud Computing is basically internet based computing. Cloud Computing can also be defined as a computing technique where we use internet i.e. ‘the cloud’ for storage and other computational purposes rather than keeping data and other information on local servers. Using Cloud Computing jobs are done which were not possible to be done solely by an individual computer.
Cloud Computing uses methods which were used before to solve a large amount of complex problems in small amount of time. This work is done because Cloud Computing uses a large amount of personal computers for providing facilities but these computers run on low power consumption. Cloud Computing connects large group of servers which makes the goal of Cloud Computing possible.
The specifications which are required for providing Cloud Computing is not defined till now. Some of the companies which provide the facilities of Cloud Computing are IBM, Amazon web services, Google App Engine etc.
Only because of Cloud Computing dreams of small business have come true. As using Cloud Computing they can just pay for the amount of facilities they use because when the company is at small scale then there are chances of modifications in the requirements and one can’t bear to pay for something they are not using.
It is said that Cloud Computing shares characteristics with some of these like client-server model, grid computing, mainframe computer, utility computing, peer to peer etc.
Some of the key characteristics of Cloud Computing are agility, cost, device and location independence, maintenance, multitenancy which includes centralization, peak load capacity, utilisation and efficiency, performance, productivity, reliability, scalability and elasticity, security etc.
The companies which provides Cloud Computing actually provides these services in different models which forms a stack i.e. infrastructure, platform and software as a service.
Iaas i.e. Infrastructure as a service includes virtual machines. It also includes storage where the data of the clients are stored and it also includes load balancers and network.
The second item on the stack is PaaS which stands for Platform as a Service which provides execution time and database. It also includes web servers and other development tools which can be used for developments the services.
The third and the last one is SaaS which stands for Software as a Service which includes CRM which stands for Customer Relationship Management, Email. It also includes Virtual Desktop which is used by clients and the other features are communications and games.