Web-based software that allows users to both generate and exchange content as well as offering a platform for peer-to-peer conversation. Popular social media sites include Twitter, Facebook, LinkedIn and YouTube. Also referred to, within the online community as CGM (consumer-generated content) social media forms a relatively low-cost and accessible vehicle allowing individuals to publish or access information, compared to industrial media.

See also:
Cost per acquisition (CPA)
Cost per click (CPC)
Reciprocal links
Ad rotation
Ad impression
Behavioural Targeting
Contextual Marketing
RSS
E-Marketing
User Session
Deep Linking