When people ask me what I do for a living and I tell them I develop web applications, they often give me a blank look. When that happens, I backtrack, generalize, and tell them I build web sites and they go, "Oh, okay!"

So what is the difference between a web site and a web application?

We all know what a web site is, so let's focus on web applications. Web applications, or Rich Internet Applications (RIA), are presented as either a web site or as part of a web site, but not all web sites are web applications. A web application is a web site that DOES something other than display content to the masses. It's intended for user interactions and transactions, performing actual business functions, and not simply displaying information to a user.

Ebay is a web application. So are Paypal, Twitter, Facebook, YouTube, Flickr, eHarmony, eTrade, GMail, and Wikipedia. Your bank, assuming it offers online banking, has a web application component on its site. If you can think of a site where you create an account, log in, and conduct some actual business, it's probably a web application.

By contrast, a web site usually refers to the front-end interface through which the public interacts with a business online. Web sites are typically informational in nature with a limited amount of advanced functionality. Simple websites consist primarily of static content where the data displayed is the same for every visitor and content changes are infrequent. More advanced websites may have features such as eCommerce, content management and dynamic content. Simple websites are basically clearing houses for information. The UGA Athletics Site is such a site, as are CNN.com, Nytimes.com and Nike.com.

Many large sites are a blend of the two. For example, Fidelity.com is a good example of a website with a web application built into it. A member of the general public can go to Fidelity.com and do research on current market trends, learn about the Fidelity company and the financial products they offer, learn tips on saving for retirement, etc. This part of the site is just a regular old web site.

However, if I have Fidelity accounts, I can sign on to a protected part of the Fidelity site where I can buy or sell stocks & mutual funds, track potential investments, get advice from Fidelity's advisors regarding my accounts, all through a nicely designed user interface. This part of Fidelity's site is a web application -- it facilitates business actions over the web, and I can conduct business on the site just like I could if I were sitting in a brick and mortar office.

Here at Plexus, we build web sites with an integrated content management application. So in that sense, every site we build has a web application built into it. Most of our clients don't need anything more than that, but a small percentage of our clients need their site to perform specific interactions with users. Our most recent web application is Listingtank.com, a site where renters looking for apartments can get cash rewards for a finding and signing lease through the site. Its business function is to match renters with property managers and to generate revenue for everyone involved. Is it a web site? Yes. But to simply call it a web site simply doesn't do it justice. Another client, Bulldawg Illustrated, uses their site to manage subscriptions to both their print and online publications. Another client recently built an application on their site to track data on local public health clinics.

Given this knowledge, the trick for any business with an online presence is to decide whether its web site could actually be used as a web application, and what business actions that application could conduct. Savvy business owners, such as Listingtank, have figured out how to adapt the technology we've made available to them to create a site that not only performs business functions, but is actually THE means by which they conduct business.

There are countless firms out there that can build you a web site. But can they build you a web application, customized to meet your business' specific needs? Can they take your traditional business functions and translate them to an interface allowing your customers to do business with you from their home or laptop? Plexus can. We love building web applications because each one is different, and each business has a specific set of needs. What business function do you want your web site to take on? The sky's the limit.