"Traditional Search (TSE):
Traditional search engines are based on information retrieval technologies. They implement operations such as boolean queries, proximity searches, text relevance and link analysis.
Examples: Google, Yahoo, MSN, Ask
Search 2.0 (S-2.0):
What I'm calling Search 2.0 are actually third generation search technologies. To explain the generations:
- First-generation search ranked sites based on page content - examples are early yahoo.com and Alta Vista.
- Second-generation relies on link analysis for ranking - so they take the structure of the Web into account. Examples are Google and Overture.
- Third-generation search technologies are designed to combine the scalability of existing internet search engines with new and improved relevancy models; they bring into the equation user preferences, collaboration, collective intelligence, a rich user experience, and many other specialized capabilities that make information more productive.
Examples: Swicki, Rollyo, Clusty, Wink, Lexxe"