Web 3D technology
Definition
Usually, Web 3D refers to interactive 3D technology that one can use through a web browser. However, users are usually required to install a so-called plugin.
Web 3D also can refer to technology that allows to browser the Web in 3D. See visualization.
Overview of web 3D technologies
VRML and X3D
WebGL
The purpose of Web GL is to bring hardware-accelerated 3D graphics to the Web without plug-ins. In other words, web browsers will directly support 3D graphics and lessen the need to install plugins.
Currently, (Sept. 2010), Firefox 4Beta and WebKit ?Beta (Safara/Chrome) provide partial support. It is possible to install one of these versions in addition to the stable versions, but you'll have to carefully manage your profiles.
Web GL is based on the well know OpenGL graphics API.
Flash
Flash 10 (released in 2008) does have 3D capabilities, i.e. ActionScript classes and methodes. Prior to official 3D support, many 3rd party developers did release Flash 3D products most of which are programming libraries. These libraries remain more popular than Adobe's classes but they usually rely on Adobe's framework.
There is not official 3D authoring tool from Adobe. CS4 and CS5 only provide support for 3D animation of 2D objects.
Links
Bibliography
Ortiz, Sixto Jr. (2010). Is 3D Finally Ready for the Web?, Computer, January 2010 (Vol. 43, No. 1) pp. 14-16. (Computer, (Access restricted)).