Collaborative filtering refers to

a process that automatically groups people with similar buying intentions, preferences, and behaviors and predicts future purchases.
		the two-way buyer-seller electronic communication in a computer-mediated environment in which the buyer controls the kind and amount of information received from the seller.
		the interactive, Internet-enabled system that allows individual customers to design their own products and services by answering a few questions and choosing from a menu of product or service attributes, prices, and delivery options.
		the consumer-initiated practice of generating content on a marketer's website that is custom-tailored to an individual's specific needs and preferences.
		an Internet-enabled digital environment characterized by face-to-screen exchange relationships and electronic images and offerings.

Web communities refer to

online cooperative buying centers that allow individuals to purchase at the same bulk rate as large organizations.
		customers linked by a common Internet service provider.
		virtual reality games that allow players to create their own worlds, countries, towns, etc.
		websites that allow people to congregate online and exchange views on topics of common interest.
		all customers served by a particular firm who are sent regular e-mail sales notifications and coupons from the manufacturer.

Showrooming refers to

areas in retail stores where point-of-purchase displays are used to show goods for sale.
		an arrangement whereby a firm reaches different buyers by employing two or more different retail layouts and atmospherics for the same basic product.
		competition among retail firms in different types of businesses but which sell the same product.
		retailers that utilize and integrate a combination of traditional store formats and nonstore formats such as catalogs, television home shopping, and online retailing.
		when shoppers visit a retail store to inspect merchandise, but then purchase that merchandise online, either from the store or one of its competitors.