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Living Online Module Lesson 25 — Researching on the Internet. Computer Literacy BASICS. Objectives. List some reasons for searching the Internet. Describe different search approaches. Define a search engine and explain how search engines work. - PowerPoint PPT Presentation
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Living Online ModuleLesson 25 — Researching on
the Internet
Computer Literacy BASICS
Computer Literacy BASICS2
Objectives
List some reasons for searching the Internet. Describe different search approaches. Define a search engine and explain how
search engines work. Identify some of the more popular search
engines. Describe some search tips and tricks.
Computer Literacy BASICS3
Objectives (cont.)
Copy, save, and print Web page data. Bookmark a Web site as a “Favorite” site so
you can return to it quickly. Download a file from a Web site.
Computer Literacy BASICS4
Vocabulary
Boolean logic Hits Keywords Math symbols
Related search Search engine Spider Wildcard character
Computer Literacy BASICS5
Searching Online
The Internet contains a wealth of information about any topic you can imagine.
Some reasons that people search the Internet include– Research for school assignments– Looking for medical and scientific information– Travel information and accommodations– Shopping for goods and services
Computer Literacy BASICS6
Search Engines
Search engines are programs that allow you to search for information.
There are hundreds of search engines on the Internet.
All search engines allow keyword searching. The results (applicable Web sites) returned
from your search are called hits.
Computer Literacy BASICS7
Concept-Based Search Engines
Some search engines, such as Excite, support concept-based searching.
Concept-based searching uses ICE (intelligent concept extraction) to determine what you mean when you enter specific keywords for a search.
Concept-based search engines return hits from searches based on word relationships.
Computer Literacy BASICS8
Stemming
Some search engines support stemming. When you search for a word, the search engine
also includes other “stems” of the word. For example, if you enter the search word play,
you may also get back results for plays, playing, and player.
Ex If you enter viewer(will search the root word) View and return viewing, viewers, preview , review etc
Computer Literacy BASICS9
Keyword Searches and Meta Tags
Keyword searches look for specific words within a Web page.
Many search engines use meta tags to build their search index.– Meta tags are HTML tags in a Web page that
do not display on the page but can be used to define page content.
Computer Literacy BASICS10
Keyword Searches andSignificant Words
Search engines also use significant words to build their index.– Significant words may be words mentioned near the
beginning of a page or repeated frequently throughout the page.
Some search engines claim to index all words in a Web page.
Some search engines differentiate between uppercase and lowercase keywords, but others do not.
Computer Literacy BASICS11
Keyword Search Steps
To search using keywords: Launch your browser and go to a search engine site. Enter your keywords in the form provided by the
search engine and submit the form.– The search engine examines its internal database index
looking for your words.– It returns a list of hyperlinks (hits) to Web sites containing
your words, and you can click a hyperlink to go to a site.
If you get no hits on your search, revise your keywords and submit a new search request form.
Search Engine Components
Search engines usually have three main components:
The search engine program that does the search of its database
A spider or crawler that looks for the information in the internet for keywords.
The index, which is built from information returned by the spider.
Computer Literacy BASICS12
Computer Literacy BASICS13
Search Results Window
The hits in a search results list are hyperlinks that you can click to go directly to a Web site.
Computer Literacy BASICS14
Examples of Search Engines
Altavista searched for a , an , or keywords
Computer Literacy BASICS15
Specialty Search Engines
Specialty search engines are also called category-oriented search engines(focus on a topic)
They are commonly used for– Locating people– Finding shareware and freeware– Shopping– Maps and almanac information– Career planning
Computer Literacy BASICS16
Examples of Specialty Search Engines
Computer Literacy BASICS17
Multimedia Search Engines
To find graphics, video clips, animation, and music files, use a special multimedia search engine:
mp3.lycos.com/ and www.audiofind.com provide search engines for music files.
www.corbis.com/ has the world’s largest collection of fine art and photography.
Computer Literacy BASICS18
Multimedia Search Engines (cont.)
www.ditto.com is a visual search engine for photographs and artwork.
www.google.com has an images tab. www.altavista.com has a special tab for
images, audio, and video.
Computer Literacy BASICS19
Search Tools and Techniques
Some commonly used search techniques are Phrase searching Search engine math Boolean searching Wildcard searching Title searching
Computer Literacy BASICS20
Phrase Searching
This technique is used to search for words that must appear next to each other.
Phrases must be enclosed in double quotation marks.– For example: “baseball cards”
Only sites with the exact phrase will be returned as hits.
You should capitalize proper nouns.
Computer Literacy BASICS21
Search Engine Math
Use math symbols to enter formulas or to filter out unwanted listings:
A plus sign (+) before a word means it must appear.– To search for sites that contain both cookies and
recipes, enter
+cookies+recipes
Computer Literacy BASICS22
Search Engine Math (cont.)
A minus sign (-) before a word means it should not appear.– To exclude any sites that have coconut
cookie recipes, enter
+cookies+recipes-coconut
Computer Literacy BASICS23
Boolean Searching
Boolean logic is similar to search engine math, but is more powerful.
Boolean logic consists of three operators:– AND: Search for sites that include word X
AND word Y.(few results)– NOT: Search for sites that include word X but
NOT word Y.– OR: Search for sites that include word X OR
word Y.(More results)
Computer Literacy BASICS24
An Advanced Search Form
An advanced search form for the Ask Jeeves search engine, designed to assist you in performing math and Boolean logic-oriented searches by setting text box options
Computer Literacy BASICS25
Wildcard Searches
Wildcard searches allow you to search for words if you do not know the exact spelling or to search for plurals or variations of a word.
The wildcard character (*) lets you search for any word that has the characters before or after the wildcard character.
– To search for the element potassium without knowing how it is spelled, enter:
PO* or po*ium
Not all search engines support wildcard searches.
Computer Literacy BASICS26
Title Searching
Web pages usually contain an HTML <Title> tag.
The text in that tag is displayed in a Web browser title bar when the page is loaded.
Some search engines allow you to search for specific Web page titles.
Computer Literacy BASICS27
Title Search Example
A title search for Internet Tutorials would return this Web page.
The title tag indicates the text that will appear in the title bar.
Computer Literacy BASICS28
Related Searches
Some search engines have a related search feature.
The search engine will return hits based on your search criteria and may also display a list of other sites that have information related to your search criteria.
This can greatly improve the odds of finding the information that you want.
Some sites (google)call this feature Similar pages or More pages like this.
Computer Literacy BASICS29
Related Search Example
Hyperlinks for related search
Computer Literacy BASICS30
Saving Data from a Web Page
Web browsers allow you to save a Web page or an entire Web site.
You can save a Web page as a text file or in HTML format.
Use the Save As command on the File menu in your browser and set the options you want.
After you save a Web page, you can open it from a disk in your browser.
Computer Literacy BASICS31
Copying Data from a Web Page
You can also copy specific elements of a Web page, such as an image or a block of text, to a disk and use them in a new document or file:
Select the text or image you want to copy on the Web page.
Click the Copy command on the Edit menu in your browser to copy the text or image to the Clipboard.
Then use the Paste command to paste the image from the Clipboard into a new or existing document.
Computer Literacy BASICS32
Printing a Web Page
You can print a copy of a Web page directly from your browser.
Most browsers provide previewing and page setup options that enable you to control how the Web page prints:– Select Print Preview on the File menu.– Click the Page Setup button if you want to adjust the
margins on the printed page or set print options.– Click the Print button.
Computer Literacy BASICS33
Favorites and Bookmarks
You can create Favorites or Bookmarks (depending on the browser you use) for sites you want to revisit.
Internet Explorer uses Favorites to refer to saved Web site locations:– Go to the site you want to add.– On the Favorites menu, click Add to
Favorites.
Computer Literacy BASICS34
Favorites and Bookmarks (cont.)
Once you save a page as a Favorite, just click the Favorites button and select the Web site name from the list to return to the page.– You can create folders to organize your
bookmarks and favorites.
Computer Literacy BASICS35
Downloading a File from a Web Site
You may want to download a file for many reasons: – Some sites offer shareware and freeware that
you can download for a small cost or at no cost.– You can download a patch or an update from a
software manufacturer for an application program you already have.
– You may want to download clip art or an audio or video file.
Computer Literacy BASICS36
Downloading a File from a Web Site (cont.)
Most sites provide an interface that makes the process of downloading simple.– A series of steps or dialog boxes provides
instructions about how to successfully download a file.
Only download files from sources you trust to avoid introducing a virus or spyware to your computer.
Computer Literacy BASICS37
Microsoft Office Clip Art and Media Home Page
Web sites that offer files to download, such as Microsoft clip art, usually provide an interface that guides you through the process of downloading.
Computer Literacy BASICS38
Summary
Search engines are used to find specific information on the Internet.
A search engine is a software program that creates an automated index of Web sites.
Concept-based searching occurs when the search engine returns hits that relate to keywords.
Computer Literacy BASICS39
Summary (cont.)
Stemming relates to the search engine finding variations of the word.
Keywords describe the information you are trying to locate, and most search engines support keyword searches.
Meta tags are special tags embedded in a Web page; many search engines use the tags to create their index.
Computer Literacy BASICS40
Summary (cont.)
A search engine has three main parts: the search engine software, a robot or spider that searches for keywords, and an index.
Specialty search engines focus on a particular topic.
Multimedia search engines focus on video, animation, graphics, and music.
Use double quotation marks around a set of words for phrase searching.
Computer Literacy BASICS41
Summary (cont.)
Use the plus and minus sign for inclusion and exclusion of words within a search.
Boolean searches use the three logical operators OR, AND, and NOT.
Many search engines offer advanced search options that let you filter search results with specific criteria.
The * symbol is used for wildcard searching.
Computer Literacy BASICS42
Summary (cont.)
Some search engines support title searching. A related search is a preprogrammed
question suggested by the search engine. You can save, copy, and print text, images,
and links from Web pages as well as entire Web pages.
Computer Literacy BASICS43
Summary (cont.)
For sites you will return to often, you can bookmark the Web address and add it to your Favorites folder.
When you download a file from a Web site, make sure the provider of the file is a reliable source. Most sites that provide files to download include a simple form or dialog boxes to help you through the process of downloading.