What is cloud computing?
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Let me clear some more doubts and answer some FAQ with Cloud Computing

Top 5 cloud computing service provider companies

1. AWS (Amazon Web Services)
2. Microsoft Azure
3. GCP (Google Cloud Platform)
4. Rackspace
5. IBM

All of the above provides various range of services with Cloud computing
For an eg. AWS provides

EC2 as a web server,
RDS as a database server,
S3 as Object storage,
API gateway to route traffic,
Cloudfront as CDN,
SES for Email sending
and many more

Similar types of services are available with all leading providers.

Do I need a big budget for cloud computing?

No, almost all major cloud providers provide “Pay as you go” model. In which you only pay for services that you choose to use. No upfront charges and no commitments are required.
That gives you the freedom to anytime switch services or providers.

How does my application fit into cloud computing strategy?

It depends upon in which cloud computing model your application fits in. So that arises a question what models are they. 

3 Main Cloud Service Models

1. Software as a Service (SaaS)
   With a SaaS product, the consumer simply accesses the product through their browser and doesn’t have to be concerned with installations or updates. 
   Think of any portal where you can login or use any services they provide and take benefit or knowledge from it.  It can be a web application or mobile Application as well. 
   Skype, Slack, Gmail are some of examples
2. Platform as a Service (PaaS)
   You can think of PaaS offerings as a curated set of services that work together to solve a large business need. For example, a business may want to create a modern microservices-based product, use remote developers, and have the product readily accessible with no delays around the world. You will hire all of that require on requirement basis, by that you need not be worried about giving infrastructure or long time commitment to them. This frees the customer to focus on the business and creativity of the product, instead of additional concern over infrastructure.
3. Infrastructure as a Service (IaaS)
   IaaS is the public cloud environment at its lowest commoditized levels. The big offerings such as AWS, Azure, and Google Cloud offer their infrastructure’s resources, network connectivity, and security compliance as a product that enterprises can use to customize as per the requirement. They provide you ready infrastructure whenever needed. and you do not need to take care of that infrastructure, just can make services or use it for purpose. 
   

What are a cloud computing deployment models?

1. Public cloud
   AWS, GCP etc are public cloud providers in which infrastructure is shared with others as Public basis(But they also provide abstraction layer as security)
2. Private Cloud
   It can be your own premise cloud or your warehouse which is only hosted and used by your company privately
3. Hybrid cloud
   It is combination of above both in which if you have some data stored in your private infrastructure but applications are hosted on public cloud, then they can access on premise data when needed.