Skyline College Library

 

Finding Information on the Web

Various types of "tools" are available on the Internet to help you find the information you need on specific topics. The different types of tools are described below, with links to specific examples of each different type and to instructions on how to use many of the specific tools. Some of the sites that are listed include more than one type of tool (e.g., sites such as Yahoo! or Alta Vista include both a subject directory and a search engine at one site).
See a listing of different tools for different needs.

Also be sure to read the general tips for how to combine search words in Web search engines included at the end of this page. This will help you understand how to develop more effective searches using any of the search tools discussed.


General Directories

Internet general directories (see examples) are general subject indexes to all types of Web sites and other Internet documents in all different subject areas. Each site included in a directory is listed under one or more subject categories, as determined by the directory's indexers. The listing for each site usually includes a brief description of the site.

Directories are often a good place to start looking for information on relatively general subjects and to get an overview of what is available on the Internet in almost any subject area.

Directories can usually be used in two basic ways:

  • you can do a keyword search to see which sites have subject, title or descriptive words that match your search words, OR
  • you can browse through a list of hierarchical subject categories from general to specific until you find listings for the topic you are looking for.

There is wide variation in the number and quality of sites included in different directories, as well as in the amount of descriptive information provided for the listed sites in the various directories. Some directories, such as Yahoo! or LookSmart, try to be as comprehensive as possible, with very extensive listings.

Examples of large Internet directories:

One disadvantage of these large directories is that they usually do little, if any, review of the quality of the sites they list so you often cannot easily find which are the best sites in a particular subject area. Also, some of these directories, such as Yahoo!, will automatically switch a search to a general web search engine if the search does not find any matches in the titles or subjects of pages in its own directory. This will make the search much more extensive, but commonly will bring up many irrelevant pages in the results list.


Selective Directories

Some directories only list sites that they have selected as the best sites in various different subject areas. Some of these selective directories, that have been developed by librarians, professors or other subject experts, focus on more academic information. When using selective directories, keep your search relatively broad in scope. For example, instead of searching for "Asian elephants", search for "animals" or "zoology". These selective directories often provide many links to other specialized intermediary sites (such as subject directories and databases) which, in turn, provide links or search engines leading to more specific quality documents in a particular subject area. One special category of selective directories (listed below) focuses specifically on links to online course materials.

Examples of selective directories (* indicates Highly Recommended sites):

  • Librarians' Internet Index* (www.lii.org)- An excellent site for finding high quality resources in a range of general subject areas [Tips for searching Librarians' Internet Index]
  • InfoMine* (http://infomine.ucr.edu/)- An excellent site for finding high quality academic resources. Select "Multiple Database Searching" for most searches. [Search Tips for using InfoMine]
  • Scout Archives* (http://scout.cs.wisc.edu/archives/) An excellent site for finding high quality academic resources. [Help for searching Scout Archives]
  • AcademicInfo* (http://www.academicinfo.us/) - An excellent directory to academic sites in a wide range of subject areas
  • Internet Public Library Subject Collections* (http://www.ipl.org/div/subject/)
  • WWW Virtual Library (http://conbio.net/vl/database/) - This is a directory of directories organized cooperatively by academic institutions and organizations around the world. Different university departments or research organizations have volunteered to maintain a subject guide to web sites for their particular discipline. These guides are linked by a general index to the various general subjects covered. To use the Virtual Library, first select a general subject from the index and then look for references to your specific topic using the guide for your chosen subject.
  • BUBL Link (http://www.bubl.ac.uk/link/) - A very good selective directory maintained by British librarians.
  • About.com (http://www.about.com/) This unique site is a directory of resources organized by professional human "guides" who maintain and host areas on their specific topics, including new content, relevant links, forums, and answers to questions. It is, however, a commerical website with many ads.

Directories of Online Course Materials

  • World Lecture Hall (http://www.utexas.edu/world/lecture/) - Links to pages created by faculty worldwide who are using the Web to deliver course materials.
  • MERLOT (http://www.merlot.org) - A free and open resource designed primarily for faculty and students of higher education. Links to online learning materials are collected here along with annotations such as peer reviews and assignments.
  • MIT OpenCourseWare (http://ocw.mit.edu) - A free and open resource of MIT course materials.


Subject Directories

Subject directories (or subject guides) are sites that provide links (often with excellent annotations) to high quality sites in a specific subject area. Some examples of subject directories in higher education discipline areas:


Web Search Engines

While directories organize web sites according to subject categories, Web search engines (see examples) are search tools that allow users to search for any word in almost any site on the Internet. Search engines are useful for searching for very specific information, but they are not the best tools for finding sites on broader topics (directories should be used to find sites on more general subject areas.) Web sites that are included in search engines are not selected, organized or previewed by any humans. Search engines' indexes are created entirely by computer programs (called spiders or robots) that continuously scan sites throughout the Internet to add to or update their lists of web sites.

Since search engines' indexes of web sites are both huge and have no subject organization at all, it is very important to think carefully about what search words to use and to be aware of the different search features available before performing a search. (See the Tips for Boolean Searching on the Web and the link to the Search Tools' Features Chart listed below.) To use search engines effectively, it is usually best to combine several search words related to a search topic using the search strategy skills discussed in the Search Strategy section of Skyline Library's "Research Assistant".

Click here to read a more complete explanation of Web Search Engines (http://www.lib.berkeley.edu/TeachingLib/Guides/Internet/ThingsToKnow.html)

Recommended Web search engines:


Meta-Search Engines

Meta-search engines are special search tools that allow you to search multiple search engines at one time. Since each search engine includes a different set of sites, many search experts recommend using meta-search engines in order to perform the most extensive search possible. Although the early versions of these meta-search tools were sometimes very slow, their performance has improved considerably over the past few years. Because they search numerous search engines with a single search statement, they generally cannot include as many advanced search features as do individual search engines.

Click here to read a more complete explanation of Meta-Search Engines (http://www.lib.berkeley.edu/TeachingLib/Guides/Internet/MetaSearch.html)

Examples of meta-search engines:


Media Search Tools

Two types of tools are available to search specifically for web images and audio and video files. Media search engines search throughout Web pages to find graphic, audio or video files. Media databases search within their own special collections of graphic, audio or video files.

Media Search Engines:

Media databases:

 

Databases on the Web

One major limitation of all the web search engines and meta-search engines is they cannot search information that is available within thousands of specialized databases that are available on the Web. These databases include all types of periodical databases (databases that index articles in different magazines, journals and newspapers and may include abstracts or the complete text of articles), government databases (including a wide range of information from census data to legal codes to all types of public records), media databases, including radio and television reports and databases of all types of non-profit and commercial organizations. These databases have a unique set of information resources (e.g., a set of articles or statistical data) that are searchable with a local search engine available at the site. (These types of web databases were the topic of a Jan. 25, 2001 N.Y.Times article titled: Mining the 'Deep Web' With Sharper Shovels.) Web database directory sites list Web databases (and subject-specific search engines and directories) in all subject areas.

Examples of databases available on the Web:


Web Database Directories

To find specialized Web databases in many different subject areas, you can try using one of the general directories or selective directories listed above. When you search for databases in a directory, try searching for a subject that is somewhat broader than your specific topic and also include the word "database" in the search.

There are also some Web database directory sites that list Web databases (and subject-specific search engines and directories) in all subject areas. Lists of searchable databases on the Web are available at the following site:

Use this site to find databases or search engines on the general subject of your research.

Another way to find Web databases is by searching Google.  Simply include the term “database” in your search.  For example:  english literature database.

Once you find a database or search engine on your general subject area, you can use that subject-based search tool to search for more specific information related to your topic.
 

People Finders

Specialized search tools for finding personal email addresses, homepages and/or phone numbers:

 

Translation Sites

Specialized web sites provide immediate free translation of web pages and text:


Tips for Combining Search Words in Web Search Engines

Search engines on the Web--whether general web search engines or local search engines for particular databases--often use special search features for combining multiple search words in a single search. These special features are especially important when your search topic includes multiple concepts. See "Planning a Search Strategy" for an explanation of how to divide a research topic into concepts and organize multiple search words into an effective "search strategy". (Most web search engines typically implement these features differently than premium periodical databases, such as the InfoTrac databases). The tips below describe general characteristics common to many Web search engines, but there is no common standard--each search engine has variations.

*Before using any search engine, you should always check the instructions, help screens or other documentation that explain the specific features of that engine.

AND: many Web search engines use the + sign (often called the "require" sign) in front of words that must be included in the search, e.g., + immigration +economy is often used instead of immigration AND economy

OR: many Web search engines assume a space = OR, e.g., economy business is often the same as economy OR business

Phrases (consecutive search words): quotes must be placed around phrases in most search engines, e.g., "illegal immigration"

Truncation: only some Web search engines allow truncation; those that do usually use * for truncation, e.g., econom* finds- economy, economic, economics, economist, etc.

Search sets: Web search engines generally do not create sets for search results; instead they allow the use of parentheses (as in algebraic equations) to designate which logical operators are to be carried out first.
For example, in the following search:
("illegal immigra*" OR "illegal aliens" OR "undocumented workers") AND econom*
a search engine would first search for: "illegal immigra*" OR "illegal aliens" OR "undocumented workers" and the results of these ORed terms would then be ANDed with econom*

"Relevance ranking": a programming method that attempts to rank search results based on various factors. Different search engines use different ranking systems. Searched documents are ranked on such factors as:

  • frequency of search words in document/page
  • search words found in title or near beginning of document/page
  • search words found close to one another
  • number of other web pages that link to the page

Finding key words on a Web page: When you view pages that have been found by a search engine, you can find where the search terms are located on the page by using the Find command on the Netscape "Edit" pull-down menu.

See the: Search Tools' Features Chart for a list of search features for many of the major Web directories and search engines; or the Quick Guide comparing the basic features of the major search engines. (Both of these pages are from the "InfoPeople" Project)

 

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last revised: 12-6-06
by Eric Brenner, Skyline College, San Bruno, CA
These materials may be used for educational purposes if you inform and credit the author and cite the source as: Skyline College Library. All commercial rights are reserved. To contact the author, or send comments or suggestions, email: Eric Brenner at brenner@smccd.net