NEW YORK (MainStreet) – After months of speculation, Apple (Stock Quote: AAPL) finally unveiled its iCloud service at a conference Monday, marking the company’s all-in entry into the cloud computing market that takes its existing MobileMe service to the next level.

For many consumers, the idea of cloud computing – storing files on the internet and accessing them on a range of connected devices – may sound like a strikingly different way of operating in your day-to-day life, but in truth, cloud computing is nothing new. In fact, the chances are pretty good that you use cloud computing already.

“The cloud is pretty much mainstream today, but many people who are using it don’t realize it,” said Krishnan Subramanian, an IT analyst and blogger for Cloud Ave, a publication that covers the cloud computing industry. “Many consumers just don’t understand that services they use are cloud-based, and have probably never thought of it in this way.”

These services range from music streaming to online photo sharing features and web-based email, and include some of today’s most popular websites. And that doesn’t even take into account the many existing online storage sites that specifically identify themselves as cloud-based services.

Web-Based Email

It’s arguably the most fundamental online service, but according to Subramanian, email falls into the general category of cloud computing, whether users think of it that way or not.

As Subramanian puts it, online services like Gmail and Hotmail store users’ messages and contact lists on the Internet rather than on one’s home computer, allowing them to access this information from any device with an Internet connection. So if you use Web-based email, then congratulations, you’re already a cloud computer.

Photo Sharing

If you’ve ever uploaded a picture of your cute pet to a photo sharing site like Flickr or Webshots, then you have adopted yet another form of cloud computing. Photo sharing sites, by definition, allow users to store pictures that are kept on a server apart from an individual computer’s hard drive, and like email, they can be viewed or downloaded on any device that connects to the Internet. Indeed, even well-known retailers like CVS provide similar cloud computing technology by letting users upload photos to the company website which can then be accessed from a store to be printed out.

Social Networking

Along the same lines, Subramanian says that anyone who is a member of social networking sites like Facebook and MySpace also engages in cloud computing, as these services effectively function like a combination of email and photo sharing. You can upload and share photographs, as well as storing notes, contact lists and messages among friends and acquaintances, all of which can be accessed from multiple devices.

Document Sharing

Microsoft and Google, two of Apple’s biggest competitors, have long offered cloud computing services, though consumers may not have recognized them as such. Both Microsoft Office and Google Documents allow users to store word documents, spreadsheets and other work files to their servers, which can then be edited from any computer with an Internet connection.

Music Services

Finally, online music streaming services like Grooveshark and the Amazon Cloud Player rely on cloud computing as well, though in slightly different ways. Amazon’s player lets users upload and store their own music files, which can then be accessed by other devices. Grooveshark, on the other hand, offers users the option to upload and share their music on the site, which can then be accessed on other computers by any Grooveshark user. In this way, it’s more of a social network than Amazon’s service, but at heart, both function through the cloud.

While many consumers are already well-acquainted with these services – and will surely adopt even more as cloud computing technology continues to grow – it is essential to keep in mind a set of best practices when using them. In general, the companies mentioned here are well-known and reputable, thus minimizing the risk of using their services, but because users’ personal data is kept in places outside of a private computer’s hard drive, novice cloud users should be mindful of what information they choose to share and upload. Get the experts’ advice in MainStreet’s guide to cloud computing.

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