Now I know......

Por: kongming | |

After 3 weeks, EIR learning, I start to understand this subject. I know how this subject improve my search skills.
From the lecture note 3&4&5, I know how google works, actually there are lots of google spiders to collect the information for google. They could divide into 3 levels. First level spiders, they go to a web collecting information, and periodic visit this web for refresh information from this web.
Second level spiders, through the web's, which hv been visited by first level spiders, links, to collect information. And third level spiders would follow principle of second level spiders.

And the intitle, allintitle, site etc, they are very usefull for our research. If u put allintitle, the title should contain all the key words.

For the search engine, we also get multi-chioce-meta :

•Search engines
•Meta search engines
•Subject directories
•Invisible Web (Databases);

we could choice anyone of them, refer to ur needs.