Cloud Computing
The cloud computing term refers to storing and accessing data over the internet. It also allows you to access data from a remote server. You don't need to store any data in your hard disk of your personal computer.
Image Source: Wikipedia
As per Wikipedia, The National Institute of Standards and Technology's definition of cloud computing identifies "five essential characteristics":
On-demand self-service
A consumer can unilaterally provision computing capabilities, such as server time and network storage, as needed automatically without requiring human interaction with each service provider.
Broad network access
Capabilities are available over the network and accessed through standard mechanisms that promote use by heterogeneous thin or thick client platforms (e.g., mobile phones, tablets, laptops, and workstations).
Resource pooling
The provider's computing resources are pooled to serve multiple consumers using a multi-tenant model, with different physical and virtual resources dynamically assigned and reassigned according to consumer demand.
Rapid elasticity
Capabilities can be elastically provisioned and released, in some cases automatically, to scale rapidly outward and inward commensurate with demand. To the consumer, the capabilities available for provisioning often appear unlimited and can be appropriated in any quantity at any time.
Measured service
Cloud systems automatically control and optimize resource use by leveraging a metering capability at some level of abstraction appropriate to the type of service (e.g., storage, processing, bandwidth, and active user accounts). Resource usage can be monitored, controlled, and reported, providing transparency for both the provider and consumer of the utilized service.
Service Models
There are three main service offered in the cloud
IaaS
IaaS means Infrastructure as a service. In this type of service, you get raw hardware from your cloud provider as a service. It often offers virtual machine disk image library, raw block storage, file or object storage, firewall etc. For example: Azure VM, Amazon EC2.
PaaS
PaaS means Platform as a service. PaaS venders provide a development environment to application developer. It gives you a platform to publish without giving the access to the underlying software. For example: Web Apps, Mobile Apps in Azure.
SaaS
SaaS means Software as a service. It refers a software that you can use without purchase it. You need not any platform and infrastructure. For example: If you launch azure VM then you are not buying OS.
Image source: Wikipedia
Cloud Deployment Models
Basically, there are three cloud deployment models.
Private Cloud
The infrastructure is claimed by you or your cloud provider gives you that service. For example: Hosting your website on your servers, or hosting your website with the cloud provider on a dedicated server
Public Cloud
In the public cloud, the infrastructure is claimed by your cloud provider and server could have multiple tenants.
Hybrid Cloud
Hybrid cloud is a combination of public and private cloud. When someone use both above clouds together then it called hybrid cloud.
Image source: Wikipedia
Microsoft Azure
Microsoft Azure is a technology which is based on cloud computing. Azure was launch by Microsoft in Feb 2010. It is a cloud platform that offers data storage, service management and service hosting over the internet. It is used to accessing infrastructure of Microsoft for cloud. Azure integrates the cloud services that you need to create, test, send, and deal with your applications, all while taking advantage of the efficiencies of cloud computing.
Summary
This is the basic concept of cloud computing that helps you know about cloud services. All described terms are often asked by an interviewer. I hope you understand. Stay with us to learn more about Azure services. Thanks.