Lesson 7:
"Invisible" or "Deep" Web

When pages are created on the fly, in response to any kind of query, the results are not saved. This means they cannot be seen by the traditional tools used to capture web page contents.

Other documents are not “normal” web pages, so the spiders also have difficulty capturing them for their indexes.

The term “invisible web” was first coined to represent this “invisible” content, but since it’s really not invisible, just more deeply buried, the term “deep web” is considered more accurate.