These two quotes from the former and current Microsoft CEO highlight the importance of the cloud. The cloud has been one of the hottest buzzwords over the last few years but you shouldn't be surprised to know that we have been using the cloud for a decade, maybe more, without realizing it. Gmail, Facebook, Skype, Dropbox, OneDrive, and so on are all examples of cloud solutions that we use almost everyday.

Cloud computing is an information technology (IT) paradigm that enables ubiquitous access to shared pools of configurable system resources and higher-level services that can be rapidly provisioned with minimal management effort, often over the internet. Cloud computing relies on the sharing of resources to achieve coherence and economy of scale, similar to a utility. Clouds enable organizations to focus on their core businesses instead of expending resources on computer infrastructure and maintenance. Cloud computing allows enterprises to get their applications up and running faster, with improved manageability and less maintenance, and it enables IT teams to more rapidly adjust resources to meet fluctuating and unpredictable business demand.

The fundamental idea behind the cloud is that we can access all the information over the internet without worrying about detailed information about the infrastructure needed to enable it.

The cloud provides businesses and organizations with:

• Flexibility: Based on the business requirements, such as enhancing a basic plan to a premium plan, we can scale the number of servers up or down. Imagine a cake business web app. During the Christmas holiday season, the demand for cakes and thus traffic to the website increases manyfold. So to serve this increased load, the number of servers can be increased during the holiday season, and during a lean phase, it can be decreased. This flexibility is key in today's economy where businesses have to save and excel in every little margin.almost instantly by the consumer as and when needed without any human
• On-demand self-service: The services can be provisioned or decommissioned almost instantly by the consumer as and when needed without any human intervention. 
• Security: Security is paramount. Rest assured that your data is more secure in the cloud than in the desktop located at your desk or the laptop that you carry. A lost/stolen laptop is a frequently encountered issue. More than financial cost, loss of sensitive data is exorbitantly costly, not just financially but also regarding reputation and trust. The cloud gives you better security when this happens. As the data is stored in the cloud, you can access it no matter what happens to your machine. You can even remotely wipe out data from your machine, if it falls into the wrong hands.
• Cost: Using the cloud saves on maintenance costs and the high cost of hardware. No more servers, software, and update fees. You simply pay as you go and enjoy a subscription. You also save on the cost of people to procure the hardware, maintain it, and update it.
• Disaster recovery: A robust disaster recovery plan in needed for any large or small enterprise as one disaster can put you out of business. The cloud lets you do it easier than ever.
• Automatic updates: Since all the servers are off-premise on the cloud, you don’t have to worry about wasting time maintaining the system yourself. The cloud provider takes care of maintenance for you and rolls out regular software updates. This keeps you free to focus on the things that matter, such as growing your business.
• Collaboration:When your teams can access, edit, and share documents anytime from anywhere, they're able to do more things better collaboratively. Cloud-based workflow and file sharing apps help them make updates in real time and give them full visibility of their collaborations.
• Work from home: Why just home? Work from anywhere you have the internet. Yes, that's a reality with the cloud.

This and many more benefits make the cloud indispensable for any modern day IT professional. I would go one step ahead and say that: 

Next, let's have a look at different types of cloud.