Service - Separation of Users and Applications
In the very past, we bought a new computer, and then install the operating system and applications and start using it.
Recently, we bought computers with bundled applications, many of which unnecessary or unwelcome, and start to uninstall them and install what we really need and then start using it.
In the future, can we just buy a new computer and start using it right after?
Accept it or not, software upgrades fast, not slower than the double of power of CPU. We have new features every day, every hour, every minute. However, customers can not afford such upgrading expense. This is especially true when there are huge number of users, or the product is for general public. Instead of letting users dealing with complex and boring installations or upgrades, why not just let the talent computer engineers deal them more efficiently.
Internet and web service provides a possible way to separate customers from software applications. However, we don't care whether it is web based applications or not. And it is not likely that all applications will be web-based in the future. Hardware could only be replaced manually. However, software can be upgraded 'forever' with a connection to the cyberspace. No matter it is operating systems or not. Theoretically, a running process can even update itself.
Up till now, there is no OS that can get upgraded automatically without causing trouble and without human beings' interfere. Debian and Ubuntu are among the not-so-perfect ones. They are in so far the best ones. You can get your software upgraded with ease most of the time. Although they are still far from perfect.
Compared to web based applications, operating systems are far more complicated. One reason is that no matter how complex the web pages are, there is only one way to interact with them, i.e. through browsers or explorers, while a operating system has to deal with all kinds of devices as well as supporting various applications. Another reason is that there are existing standards for web pages or web services. This makes things easy and coherent.