Cloud computing is a metaphor for the internet and storing data in various locations and devices remotely. Instead of saving data locally to your own hard disk, optical media, external drive and so on, data is uploaded to a location elsewhere, accessible via the internet.
Cloud computing has existed in the 1960s, a key player in the development of ARPANET ( Advanced Research Projects Agency Network), JCR Licklider proposed an idea of an “intergalactic computer network.” This sound a little silly if taken literally, but the term wasn't literal in regard to actual scale, but was instead an idea focused on people around the globe being connected to each other, able to access data and programs anywhere.
Many may think Licklider's description sounds like the internet we know today, and in some regards it is, but the key here is being able to access data and programs from any site. The internet allows this in a way, but not in the some manner as actual cloud computing, which focuses on the storage and access of data rather than hosting of web services and sites.
Later in 1999, a major landmark in cloud computing arrived, as Salesforce.com lunched its delivery of application to an enterprise user base via a website. Long before the emergence of today's big names like Microsoft and Google, online applications and collaboration were available to business users before the turn of the millennium.
Amazon was the first widely accessible cloud computing infrastructure service. The Google and Microsoft. Of course, this progressive popularity of cloud application did not just arrive on its own, and it was only made possible by the growth of other technologies that run behind the scenes. In particular, virtualisation is a key component of any cloud service. Virtualisation is used in various forms when it comes to cloud computing, mostly in terms of streamlining server farms, making it possible to host many more machines in any given space while saving energy and being more efficient.
A major problem that remain prior to cloud computing's arrival in the mainstream market was security. This is still a concern for many, especially home users, and the idea of hosting information remotely or accessible from any location presented a real problem. Although the idea of accessing data from anywhere at time bore obvious benefits for business and remote workers, the security needed to ensure data was still safe paramount. Many industry users were primarily concerns with this, and a heavy focus on general security was needed for cloud computing to take off.
Fortunately, security concerns were alleviated for the most part, with secure web portal logins, encrypted communications and other methods of user identification. These days, there are various layers of security and more stringent checks in place to protect any remote data. In fact, in many instances, data you store remotely vie the cloud is likely more secure than it is on your own home PC, because it sits on network infrastructure designed with security in mind.
Cloud computing now sits in a very comfortable spot, and many experts predict that the cloud represents the future of computing. Home PC will eventually be little more then terminal for many users who need basic access to the internet and applications, and when it comes to business use, where keeping costs low is essential, this makes even more sense. No longer would companies need to invest in the own PC infrastructure as we know it now, and a basic network with terminals accessing the internet cloud replace many setups.