Desktop Widgets vs Web Widgets:
Widgets are one of the most confusing areas of Web 2.0. Not only is the term "widget" used to refer to desktop and web-based widgets, but the word "gadget" is also sometimes thrown into the mix. And, like widgets and gadgets, the differences between a web widget and a desktop widget are slim.
What is a Web Widget?:
A web widget is a piece of code that can be used to enhance a personal web site, start page, blog or social networking profile. They are web-based, which means they can only be part of a website. You cannot put a web widget on your desktop without someone writing an application around that web widget.
If you've ever seen a YouTube video being displayed on a website other than YouTube, then you've probably seen an example of a web widget.
What is a Desktop Widget?:
A desktop widget is a mini-application that accesses the Internet to provide you with information. For example, a weather widget that displays the temperature and forecast for your area might read this information from Weather.com.
Desktop widgets often require a separate application as a "holder". For example, Yahoo! Widgets require you to install the Yahoo! Widgets toolbar. This application "holds" the Yahoo! Widgets and allows them to be displayed on the desktop.
So, What's the Deal? When Should I Use One Over The Other?:
The main difference between a web widget and a desktop widget is that a web widget requires you to be on a certain website while a desktop widget can always be displayed on your computer regardless of what web page you are viewing.
Desktop widgets are best for those things that will be commonly used like a weather widget or a widget that displays local news. Anything that might be of interest throughout the day.
Web widgets have many different uses. You might put a widget on your personalized start page that displays headline news or gives you stock quotes. You might put a widget on your blog to entertain your readers. You can even decorate your social networking profile with widgets.
In essence, web widgets travel better, while desktop widgets are more stable.