Google Hacks 2Nd Edition [Electronic resources] نسخه متنی

Hack 1. Browse the Google Directory

Google has a searchable subject index in
addition to its eight-billion-page web search .

Google's Web Search indexes over eight billion pages,
which means that it isn't suitable for all searches.
When you've got a search that you
can't narrow down, like if you're
looking for information on a person about whom you know nothing,
billions of pages will get very frustrating very quickly.

But you don't have to limit your searches to the
Web. Google also has a searchable subject index, the Google
Directory, at http://directory.google.com. Instead of
indexing the entirety of billions of pages, the directory describes
sites instead, indexing about 1.5 million URLs. This makes it a much
better search for general topics.

Does Google spend time building a searchable subject index in
addition to a full-text index? No, Google bases its directory on the
Open Directory Project data at http://dmoz.org/. The collection of URLs at
the Open Directory Project is gathered and maintained by a group of
volunteers, but Google does add some of its own Googlish magic to it.

As you can see in Figure 1-6, the front of the site
is organized into several topics. To find what
you're looking for, you can either do a keyword
search, or drill down through the hierarchies of
subjects.

Beside most listings, a couple of which are shown in Figure 1-7, you'll see a green bar. The
green bar is an approximate indicator of the site's
PageRank in the Google search engine. (Not every listing in the
Google Directory has a corresponding PageRank in the Google web
index.) Web sites are listed in the default order of Google PageRank,
but you also have the option to list them in alphabetical order.

One thing you'll notice about the Google Directory
is how the annotations and other information varies between the
categories. That's because the information in the
directory is maintained by a small army of thousands of volunteers
who are each responsible for one or more categories. For the most
part, annotation is pretty good.

1.13.1. Searching the Google Directory

Because the Google Directory is a far smaller collection of URLs,
ideal for more general searching, it does not have the various
complicated special syntaxes for searching that the web search does.
However, there are a couple of special syntaxes that you should know
about.

intitle :

Just like the Google web special syntax, intitle:
restricts the query word search to the title of a page.

inurl :

Restricts the query word search to the URL of a page.

When you're searching on Google's
web index, your overwhelming concern is probably how to reduce your
list of search results to something manageable. With that in mind,
you might start with the narrowest possible search.

That's a reasonable strategy for the web index, but
because you have a narrower pool of sites in the Google Directory,
you want that search to be more general.

For example, say you were looking for information on author P. G.
Wodehouse. A simple search on P. G. Wodehouse in
Google's web index will get you over 86,000 results,
possibly compelling you to immediately narrow down your search. But
doing the same search in the Google Directory returns only 143
results. You might consider that a manageable number of results, or
you might want to start carefully narrowing down your results
further.

The Directory is also good for searching for events. A Google web
search for "Korean War" will
find you a million and a half results, while searching the Google
Directory will find just over 2,830. This is a case where you will
probably need to narrow down your search. Use general words
indicating what kind of information you
wanttimeline, for example, or
archives, or lesson
plans. Don't narrow down your
search with names or locationsthat's not the
best way to use the Google Directory.