Cloud is "the" buzzword for technology since 2010. Cloud this and cloud that. I especially like "we're in the cloud". "Cloud" as a buzzword is very poorly defined so it can have a couple of definitions.
Cloud as software services. Cloud as software services used to go under the buzzwords, ASP - application service provider and SAS - software as a service. If you've used turbotax or quickbooks online then you've used "the cloud" as software. Basically your using a browser as the GUI, visual interface, and all the logic and database functions are happening on servers somewhere. For most business users this is what cloud means. It means you'll use a computer and browser or a smartphone and with the Internet connection on those devices you'll access movies, music and data running on a company's servers. At this point you're probably thinking, okay, nothing new here.
For businesses the advantage of cloud as software services is it can take the software on a desktop model of doing business and make it centralized and cheap to offer those same software benefits to infinitely more users at rediculously small per user costs. If you own your own software, this kind of business model can tremendously benefit your business both in reducing support costs and in expanding your client base.
This blog that you're reading right now is provided by Weebly (www.weebly.com) which is web based software for creating and maintaining websites and it's hosted by their servers. If you want a basic site, I highly recommend them. The service starts as free and for a small price you get more functions (a common online business model for these kinds of services). There are many other companies that provide similar and good services. You can always search weebly review or weebly competitor on Google search to find others.
Cloud as a platform and computer power. Service companies create whole warehouses full of servers that have huge data pipes. All the functions for logic and data storage are available in that huge array of computers. Companies pay for computing power that is immediately scalable to handle huge data and customer loads. So instead of pointing at a couple of servers and saying that is my computer farm you can sweep your arms over the whole darn building and say that is my available computing power. Essentially it's computing power used as a utility, like your electric meter. You turn on your AC and the dial spins faster and you're billed more for the power use. Lots of customers hit your website and the computer "power meter" spins faster and you're billed more for the computing use. NOTE: Even with cloud platform providers there can be a lot of variation in what you need to do with your software/web applications in order to "live" on the platforms and take advantage of the computing power. Some allow you to build your software on a common software development platform like Microsoft technology and you're good. Others, like Amazon, require you to write software to their specifications. You really need your technical people to get involved in these kinds of pros and cons decisions.
For businesses the advantage of cloud as a platform is primarily you get a world class server farm that is able to handle tremendous user loads for a fraction of the price of having and maintaining in-house servers.