The concept of the "sensor web" is a type of sensor network that is especially well suited for environmental monitoring. The phrase the "sensor web" is also associated with a sensing system which heavily utilizes the World Wide Web. OGC's Sensor Web Enablement (SWE) framework defines a suite of web service interfaces and communication protocols abstracting from the heterogeneity of sensor (network) communication. (http://en.wikipedia.org/wiki/Sensor_web)
[... contributions welcome!]
SOS Tutorial at OGC Network: http://www.ogcnetwork.net/SOS_2_0/tutorial This tutorial should help non-technical SOS users to get an overview on SOS without having to read the whole specification document.
New Generation Sensor Web Enablement, Arne Bröring, Johannes Echterhoff, Simon Jirka, Ingo Simonis, Thomas Everding, Christoph Stasch, Steve Liang, Rob Lemmens Sensors 2011, Volume 11, Number 3, 2652-2699 open access publication. A good paper describing all relevant standards, their challenges, and what was changed to work towards a "Sensor Web 2.0".