FIRST GENERATION TOOLS:
DEFINITION AND CLASSIFICATION
The first generation of search tools are "server-side" systems (all the information and the engines to use them is at the other end of the connection) aimed at locating and recovering information from the World Wide Web using the added-value provided by:
1. the brute-force of large search engines (with huge resources compiled by robots traversing the net) with sophisticated algorithms and supporting powerful Boolean interrogation languages,
or
2. the human evaluation of the resources, with indexers that provide keywords and descriptions for each website so later it could be possible to organize them according to a classification (thematic or geographic).
Thus we have the basis for a simple classification, with an indication about the best strategy for recovering data in each situation:
CATEGORIES |
COMPILING E INDEXING METHOD |
PRECISION |
EXHAUSTIVENESS |
RECOVERING RESOURCES |
I. INDEXES |
HUMAN ASSISTED |
+ |
- - |
BY NAVIGATION |
II. SEARCH ENGINES (DATABASES) |
COMPUTER ASSISTED |
- |
+ + |
BY SEARCH STRATEGY |
The double plus sign (++) means that the search engines are more comprehensive not only in the coverage of the full text of a site but also on the total number of sites downloaded to the database.
