March, 2010. [Note: some of these links may no longer work.]

What is the difference between Cloud-based applications and Web-based applications? I think that Web-based applications are now a subset of Cloud-based applications as I define them (if you don't like my definition this won't work) and I think I can use Facebook to show why this is.

Wikipedia today defines a Web application (to which "online application" redirects, so I'm talking about those too) like this:

"In software engineering, a web application is an application that is accessed via a web browser over a network such as the Internet or an intranet."

which seems perfectly reasonable to me. I'll also equate "web application" with "web-based application." So Facebook can be accurately described as a web or web-based application. Fair enough. But now I can access it via my iPhone. Fine. It's "a web-based application I can also access with my iPhone app." Fair enough.

But what if the web interface goes away, meaning Facebook stops using it, because they who own Facebook decide that mobile phones are The Wave Of The Future (which they might very well be) and who wants to bother with the borin' ol' web? Which they won't (presumably) but what if they did? Then what is Facebook? I can't call it an iPhone app. That's the thing on the phone. Luckily I have defined Cloud-based applications and data like this:

Cloud-based applications and Cloud-stored data (as I use them) are applications and data I use that are not on my network-connected device but somewhere (I may or may not know exactly where) on other computing and storage devices connected to the network (in "the Cloud") which I connect to over the network.

which comes to the rescue. Because my iPhone is the "network-connected device" and the application and data I am connecting to are out there somewhere in the Cloud (somewhere on those computers whose location I don't really know; I mean Facebook controls them but I don't know where they are exactly). This means Facebook is a Cloud-based application.

But now what happens if they who own Facebook add back the Web interface? Well, I can call my computer with which I access the Internet my "network-connected device" and still the application and data are out there somewhere. So Facebook is (still) a Cloud-based application, one I connect to with both my laptop and my iPhone (network-connected devices) over a network (the Internet or a cell-phone network or whatever).

I think the programs that access Facebook in these two cases - the web browser or the iPhone app - can be called, in this context, access programs.

In other words, now that smartphone apps have turned up I figure I can call "Web-based" applications a subset of a larger group of applications called "Cloud-based." Now that only works if you agree with my definition of Cloud-based, so if you don't all bets are off.

But it seems reasonable to me, a guy grappling with technology. All comments welcome.

p.s. I've checked the Cloud Computing entry (there is no "Cloud-based computing" entry) on Wikipedia which I understand better now. You might like to check it out. If you do the section on the Discussion page entitled The lead, one sentence. That's all I ask makes for interesting reading. In this section people discuss whether the term "Cloud Computing" can have a one-sentence definition and if so what that is. It's a fairly long discussion among experts. That's why I use "Cloud-based computing." It may seem like a subtle distinction but it's easier for me to understand. Just as someone who is a "technology-grappler."