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Finding Information
on the Web
Advanced Search Techniques
Outline
- First: Some Background
- Second: A Classification of Web Search Tools
- Third: An Example & Comparison of Web Search Techniques
- Finally: Some Special Search Tools and Features
- Postscript: For More About Web Searching....
First: Some Background
- The Internet
- What is it?
- It's not just another name for the Web - it includes more.
- It's really an "infrastructure" - A "network of networks", that all talk the same language ("TCP/IP")
- What does it include? Some examples:
- ftp ("file transfer protocol")
- telnet
- WWW
- and other stuff...(anybody remember "gopher"?)
- The Web
- The Web is part of the Internet - an Internet information system characterized by the use of "hypertext"
- Features of the Web as an Internet information system:
- A communications protocol:
HTTP - HyperText Transfer Protocol- A "markup" (i.e., screen display) language:
HTML - HyperText Markup Language- A global document addressing scheme:
URL - Uniform Resource Locator- The make-up of a Web address (URL):
e.g., http://www.library.ubc.ca/home/websearch/quick.html
- protocol: http
- host or domain name: www.library.ubc.ca
- path: /home/websearch
- document file name: quick.html
- Modern Web browsers -- e.g., Netscape Navigator, Internet Explorer -- can handle multiple Internet protocols besides http (e.g., telnet, ftp, smtp (email), and more).
- Setting Expectations, Evaluating Sites Found:
- First, not everything is on the Internet (yet)
- Contrast the Wild World of the Web to the structured world of library indexes and databases.
- The Web is uncontrolled and unfiltered -- which is what makes searching it such a challenge
- What is on the Web:
- Lots -- from government documents, to preprint archives, to spoofs.
- Evaluating what's found: here are some familiar evaluation criteria that acquire added importance when assessing Web search results:
- credibility - is the source or author identified, and are there any indications of credentials?
- objectivity or bias - is the page part of, or produced by, a site with an agenda, or with conflicting interests?
- currency and feedback - is the page dated, and does it provide any means of emailing, or getting in touch with its producer?
- Here's a page that provides more information about evaluating Internet resources
S econd: A Classification of Web Search Tools
There are a lot of different Web search tools - but they can be grouped into a few general types or classes, as follows (notice that Yahoo, for example, is in a different class from AltaVista):
Search Engines
Also known as "Keyword Indexes", these are large, comprehensive indexes that require you to type in the terms that define your search.
Example:
Other Examples: Subject Directories
These classify a small subset of the Web into subject catogories and sub-categories. Can be searched by keyword or by "drilling down" through the categories.
Example:
Other Examples: Britannica | Clearinghouse | INFOMINE | Internet Public Library (Ready Reference) | Looksmart | Magellan | WWW Virtual Library | Yahoo
Name Directories
These are the White Pages and Yellow Pages of the Internet.
Example:
Other Examples: Canada 411 | Postal Code Lookup (Canada Post) | Big Book (US Yellow Pages) | Sales Leads USA
Meta-Searchers
These are tools that submit a search to a number of other search tools automatically.
Example:
Other Examples: Cyber411 | ixquick | Mamma | MetaCrawler | Search.com
Specialized Search Tools and Searchable Databases
Already focused on a particular subject or Internet area, these can be the most precise and powerful of all Internet Search tools.
How do you find these specialized tools? Using Subject Directories (see above) and Collections of "Searchable Databases", providing access to the so-called "Deep Web", an information repository as much as 500 times the size of the Web visible to search engines.
Example:
Other Examples:
T hird: An Example & Comparison of Web Search Techniques
- Different search tools vary widely both in the kinds of search techniques they allow, and in the "syntax" or means by which they express those techniques. We'll look at the following examples of search techniques, using two of the most popular search tools: AltaVista and Google:
- Match Any or match All
- Match an exact phrase
- Exclude a word or phrase
- Using "wildcards"
- See "Power Searching for Anyone", by Danny Sullivan, for more about search tool syntax.
Finally: Some Special Search Tools and Features
This sampling is intended just to give you an idea of the rich variety of search features and functions that are available.
- Specialized multimedia searches: AltaVista
- Automatic Translation: AltaVista
- News sites: Moreover
Postscript: For More About Web Searching...
- Searching the Internet: Recommended Sites and Search Techniques
by Laura Cohen, from University at Albany Libraries, this is an excellent recent treatment; see her other guides at this site as well, especially Conducting Research on the Internet
- Search Engine Showdown
by Greg Notess -- not quite the confrontation implied by the title, this site presents the various search tool features in short, nicely summarized tables.
- Search Engine Watch
from Danny Sullivan -- more for the dedicated Web searcher (or Web Manager), this also includes links to some useful, up-to-date reviews and tutorials for novices.
- About.com's Web Search
from Kevin Elliott -- topical and popular.
Finally, here's the UBC Library Internet Search Tools page.
(You can get to it by clicking on "Internet Search" on the bottom bar of the Library Home Page, or on "Internet" on the navigation bar at the top and bottom of most Library Web pages.)