Here’s some examples:
This is web delivered software accessible from a computer with a web browser. There may still be requirements set by the software developer such as ram, operating system, or certain type of web browser. It is subscription based, without the traditional requirements of having software installed and running from your internal network.
This may also be called “Offsite Backup” to a data center or multiple data centers. Your data is remotely transferred over time to a secure data center for when a disaster occurs. Data retrieval is through the web.
Common product names are Dropbox, Skydrive, JungleDisk, FilesAnywhere, and iCloud. This is virtual storage for you to save documents, pictures, and files of any type for access through the web. This is great for collaboration. This is not great for very large file storage and retrieval because of speed limitations over the web.
This is storage shared with other people on the same equipment. You cannot see anything but your data, and other people cannot see your data, but you are sharing the same virtual space.
This is storage that is not shared with anyone else, and is run on your equipment only, usually from a data center.
This is a combination of local server hardware, server virtualization, and cloud delivered software in a subscription model.
This is everything delivered via the web. Full desktop virtualization brought down through any device, anywhere, through a login and password via your web browser. Your same desktop brought down every time no matter what computer you use, or what operating system. Your server is virtual, your data is stored virtually, all you need is access to the web.