| Lesson 5 || Search Engine Course exercises |
| Objective || Learn about the two types of exercises in this course. |
Understanding Search Engines
During this course, you will acquire a wide range of skills and techniques that are applicable to your own needs for
locating information that
is stored in the tens of millions of Web sites on the Internet.
To assist you in applying these skills and to help you focus on how you might best use them,
you will encounter different types of exercises in this course.
What Is a Search Engine?
The basic concept of a search engine is to type a word or phrase into a search box and click a button. Wait a few seconds, and references to thousands or millions of pages will appear. Then all you have to do is click through those search engine result pages to find what you want. But what exactly is a search engine, beyond this general concept of entering text into a textbox?
On the back end, a search engine is a piece of software that uses applications to collect information about web pages.
The information collected is usually key words or phrases that are possible indicators of what is contained on the web page as a whole, the URL of the page, the code that makes up the page, and links into and out of the page.
That information is then indexed and stored in a database. On the front end, the software has a user interface where users enter a search term in an attempt to find specific information. When the user clicks a search button, an algorithm then examines the information stored in the back-end database and retrieves links to
web pages that appear to match the search term the user entered.
The process of collecting information about web pages is performed by an agent called a crawler, spider, or robot.
The crawler literally looks at every URL on the Web, and collects key words and phrases on each page, which are then included in the database that powers a search engine. Considering that the number of sites on the Web went over 1 billion some time ago and is increasing by more than 1.5 million sites each month, that is like your brain cataloging every single word you read, so that when you need to know something, you think of that word and every reference to it comes to mind.
The best way to develop proficiency in Internet searching is through practice.
As a new technique or resource is introduced in a lesson, you will have the opportunity to use it in a searching exercise.
Usually, links to two or more search sites will be displayed, and you will be asked to compare the results. The topics and information that you will search for are, of necessity, somewhat generic; you should feel free to add or substitute topics that are of specific interest to you.
On Your Own exercises
On Your Own exercises are more about thinking than they are about doing, and they are in the course to help you think about the ways that improving your ability to find information on the Internet can be of benefit to you.
This may be especially valuable if you are new to the Internet or new to using directories (like Yahoo!) or search engines excite.
You may find it useful to actually keep a list of ideas and search topics to check as you progress through the course.
If you find yourself unable to think of an answer, you may want to check the Discussion area for suggestions.
If you are a more experienced Internet user and searcher, you may find value in reflecting upon your own experiences.
Successes and frustrations in deciding which techniques and searching resources might be of the most use to you.
The next module will discuss some of the types of information available on the Web, introduce you to information retrieval services, and describe some of the challenges to finding exactly what you want.