This is “Introduction”, section 6.1 from the book Getting the Most Out of Information Systems (v. 1.2).
This book is licensed under a Creative Commons by-nc-sa 3.0 license. See the license for more details, but that basically means you can share this book as long as you credit the author (but see below), don't make money from it, and do make it available to everyone else under the same terms.
This content was accessible as of December 29, 2012, and it was downloaded then by Andy Schmitz in an effort to preserve the availability of this book.
Normally, the author and publisher would be credited here. However, the publisher has asked for the customary Creative Commons attribution to the original publisher, authors, title, and book URI to be removed. Additionally, per the publisher's request, their name has been removed in some passages. More information is available on this project's attribution page.
For more information on the source of this book, or why it is available for free, please see the project's home page. You can browse or download additional books there. You may also download a PDF copy of this book (25 MB) or just this chapter (1 MB), suitable for printing or most e-readers, or a .zip file containing this book's HTML files (for use in a web browser offline).
Network effectsAlso known as Metcalfe’s Law, or network externalities. When the value of a product or service increases as its number of users expands. are sometimes referred to as “Metcalfe’s Law” or “network externalities.” But don’t let the dull names fool you—this concept is rocket fuel for technology firms. Bill Gates leveraged network effects to turn Windows and Office into virtual monopolies and in the process became the wealthiest man in America. Mark Zuckerberg of Facebook, Sergey Brin and Larry Page of Google, Pierre Omidyar of eBay, Andrew Mason of Groupon, Evan Williams and Biz Stone of Twitter, Nik Zennström and Janus Friis of Skype, Steve Chen and Chad Hurley of YouTube, all these entrepreneurs have built massive user bases by leveraging the concept. When network effects are present, the value of a product or service increases as the number of users grows. Simply, more users = more value. Of course, most products aren’t subject to network effects—you probably don’t care if someone wears the same socks, uses the same pancake syrup, or buys the same trash bags as you. But when network effects are present they’re among the most important reasons you’ll pick one product or service over another. You may care very much, for example, if others are part of your social network, if your video game console is popular, and if the Wikipedia article you’re referencing has had prior readers. And all those folks who bought HD DVD players sure were bummed when the rest of the world declared Blu-ray the winner. In each of these examples, network effects are at work.
The term “network” sometimes stumps people when first learning about network effects. In this context, a network doesn’t refer to the physical wires or wireless systems that connect pieces of electronics. It just refers to a common user base that is able to communicate and share with one another. So Facebook users make up a network. So do owners of Blu-ray players, traders that buy and sell stock over the NASDAQ, or the sum total of hardware and outlets that support the BS 1363 electrical standard.