What is The Cloud?

The Cloud is made up of two important things, they are

• Virtualization
• Automation

These two provides users access to a lot of services on an infinite scale at affordable prices.
By virtualization it means you need not always have your own copy of a hardware or software, it can be shared among all the users.
Automation provides self-service, infinite scale and utility-based pricing and services. In the cloud, based on the traffic to a website, it can easily be made run on multiple servers if traffic is high and on a single server if traffic is very low.

Types of Cloud :

• Public: It is a leased cloud from provides which is mostly available at low cost. 
• Private: It is your own hardware in the house on which the cloud runs. It is fixed cost and has low scaling due to limited servers. The user has full control of the cloud.
• Hybrid: It is the combination of both public and private. It provides control where you need and scale when you need based on the requirements.

• at the Application level, it is known as Saas(Software as a service). eg web services
• at Platform level it is known as Paas(Platform as a service). eg  Development
• at Infrastructure level it is known as Iaas(Infrastructure as a service). eg servers