The desktop you use today is probably from one of the larger traditional software vendors. The underlying concepts and designs of these desktops date back to pre-Internet ages. Back then, a computer was a data processing machine and the user a data processing manager. As you know many things have changed since then. icloud was designed from the ground up to meet the demands of today's Internet savvy user community. The icloud desktop was designed around the Internet at its core. Your desktop, applications, and files reside securely in icloud's data centers and are easily accessible from anywhere using your own computer or a friend's.
icloud is designed to remove all footprints and traces of your activities at the end of each session when you close down your browser, i.e. your privacy is protected at all times. icloud is also environmental friendly. Since icloud runs within your web browser it doesn't consume much power from your computer. As a matter of fact, even older "outdated" computers run icloud very well.