Web 2.0 Properties
Web 2.0 properties have become the crest of innovation in SEO, being the latest technology that allows you to get highly oriented traffic. These properties can be defined as user-generated content web pages, which allow users to interact and collaborate with each other.
Think of it as a community, where you can build a reputation due to highly relevant and keyword-focused content. Links coming from these properties are of great value for search engines and allow you to avoid Google Panda & Penguin.