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CNIT131 Internet Basics & Beginning HTML

Learn about how search engines work, including their complex algorithms, factors that determine search rankings, and the search process. Discover trends and developments in search engine algorithms and how to evaluate search tools for the most relevant results.

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CNIT131 Internet Basics & Beginning HTML

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  1. CNIT131 Internet Basics & Beginning HTML Week 04 – Searching the Web http://fog.ccsf.edu/~hyip

  2. The Search Process

  3. How Search Engine Work? • Search engines use complicated, patented, everchanging algorithms to create search rankings, which determine the order in which suggested content appears in the search results. • Search engine algorithms instruct the search engine to locate and rank search results based on keywords and a variety of other factors. In addition to using programs called crawlers to locate webpages, search engines determine relevancy of search results based on page rankings, frequency of content updates, keywords and metadata, and number of inbound and outbound hyperlinks. • In addition, search engines may use analytical tools to rank search results based on factors such as number of website visitors, trending topics, and more.

  4. How Search Engine Work? (2) • Google, Bing, Yahoo! and other search engines keep their search engine algorithms private. By not disclosing search engine algorithms, the search engines are attempting to prevent search engine optimization (SEO) marketers from manipulating web content to improve search rankings in order to have them appear higher in search results. • Other trends and developments in search engine algorithms include: • Personalized searches based on a user’s previous search history. • Localized searches that provide results targeted to a user’s geographic location. • Analysis of popular search terms in order to improve the algorithms. • Increased focus on social sharing by analyzing trending and commonly shared web content on social media platforms such as Facebook and Twitter. • Focus on natural language searches that use phrases or questions rather than keywords. • Banning or removing webpages from the search engine index if they use manipulative or unethical SEO practices, ensuring the best search results for users

  5. How Search Engine Work? (3) • In general, when evaluating search tools, look for tools that: • Are easy to use • Return search results quickly • Provide access to frequently updated large indexes of webpages and other webbased files • Present the most relevant search results for a keyword search • Clearly indicate paid or sponsored links in their search results list

  6. Specialized Search Engines

  7. Formulating the Search Query • A search query is a question that defines the information you seek. • A query should include at least one keyword, a specific word that describes that information. • To get the best results, choose keywords carefully and use specific rather than general keywords whenever appropriate. • You enter search keywords in a search tool’s search text box or in the Address box. • The search tool then uses the keywords to identify relevant webpages and return a search results list containing the URL, title, and description of and links to webpages that the search tool determines to be the most relevant to the keywords. • Each webpage item listed in a search results list is a hit.

  8. Formulating the Search Query (2) • A targeted search seeks specific information using keyword combinations. • An open-ended search seeks information on a broader scale using a simple keyword. • Many search tools allow natural language searches, such as Ask.com. • A natural language search puts the query in the form of a statement or question. A natural language search for the Canadian capital is: What is the capital of Canada? The search engine ignores small, unimportant words in a natural language search query, called stop words, and only uses the more important, specific words in the search. Examples of stop words include what, where, is, the, of, in, and how.

  9. Evaluating the Credibility of Search Results • AUTHORITY: The first step in determining the quality of the information on a webpage is to examine its authority. To do this, determine who owns or sponsors the website and, if possible, who authored the page content. A primary source is any document, item, or other data that provides firsthand information about a particular topic. • OBJECTIVITY: When examining a website’s objectivity, determine whether the webpage information is presented fairly, whether the content contains any subtle or clear biases, or whether the information is skewed toward commercial or political interests.

  10. Evaluating the Credibility of Search Results (2) • SCOPE AND QUALITY: Evaluating the scope of webpage content — the depth of coverage and the amount of detail provided — can help determine its value. Additionally, high-quality webpage content should be accurate and up to date. Verifying facts and statements on a webpage with other web resources is a good way to verify accuracy. Look to see if the article or webpage has a time or date of posting listed to determine its timeliness. One technique for determining scope and quality is to compare the information on several webpage sources that discuss the same topic. • DESIGN AND FUNCTIONALITY: Your first impression of the website also offers insight to its credibility. Webpages with grammar or spelling errors, poor organization, missing images, or broken links — links that no longer work — at best indicate poor attention to detail, and at worst might indicate the page is a poor-quality source.

  11. Evaluating the Credibility of Webpages Questions to ask when evaluating the credibility of webpages.

  12. Search Tools - Directories • A directory is a human-compiled, hierarchical list of webpages organized by category. • One of the first directories was created by Jerry Yang and David Filo, two doctoral students at Stanford University, who began to keep a list of interesting webpages for their personal use. • Their Stanford classmates and friends soon began asking to share the list, originally called Jerry’s Guide to the Web. • Soon the list became long and unwieldy, so Filo and Yang divided the list into categories and then later, as the number of webpages continued to grow, into subcategories. • In 1995, the Jerry’s Guide directory was renamed Yahoo!. The original Yahoo! directory has evolved to become the Yahoo! network of online tools and services, including Yahoo! Search, Yahoo! Directory, Yahoo! Mail, Yahoo! Shopping, and more.

  13. Search Tools – Directories (2) • A staff of human editors compile directories and create an index, or list of webpages. Directories are useful search tools that present links to websites organized into easily understood categories. • Using human editors to compile a directory’s index of web resources is both a strength and a weakness. • Human editors can organize lists of web resources in a logical way, making browsing or drilling down through a directory’s categories an organized process. • Using human editors also is a disadvantage, however, because of the time it takes for human editors to review new webpages and add them to a directory’s index. • Additionally, human editors determine what pages to accept for the index and what pages not to accept. Using a directory, therefore, might not provide links to a number of appropriate and useful webpages on any particular topic simply because the editors have rejected or not yet added the webpage to the index. In addition to the DMOZ Open Directory Project, other directories include Yahoo! Directory and Business.com.

  14. Search Tools – Search Engines • Search engines for computers and mobile devices include general-purpose search tools, such as Google, Ask.com, Bing, and Gigablast. • Additionally, specialty search tools, such as Bizrate (shopping), Fact Monster (kid-friendly searches), and Technorati (blogs and other user-generated media), abound. Some search engines, such as Google, provide search technologies or webpage indexes for other search engines. • A search engine uses software called a spider, bot (short for robot), or web crawler that browses the web, automatically adding the URLs and other information about webpages to a searchable index. Yahoo! Slurp, Googlebot, and Bingbot are all examples of web crawlers. Web crawlers provide and categorize content for search engines. Users do not interact directly with web crawlers.

  15. Search Tools – Search Engines (2) • web crawlers typically scan for some or all of the following information to create their indexes: • Page title—coded title that appears on the browser title bar when the webpage opens • URL—specifically, the domain name • Meta tag keywords — descriptive keywords coded into the webpage’s HTML code that are readable by the web crawler but invisible to the user • Occurrence of keywords—both the frequency of use and where they appear on a webpage • All of the words on the webpage, which is known as full-text searching • Internal links within the webpage to other pages on the website • Number and relevancy of other webpages that link to the page

  16. Search Tools – Search Engines (3) • Web servers store the webpage information retrieved by a web crawler in a database, creating an index. Web crawlers continually browse the web to update their indexes with modified webpage content or new, previously unknown webpages. • When a user interacts with a search engine, it accesses the results of the web crawler’s searches, but doesn’t interact with the web crawler directly. • When a user enters keywords into a search engine’s search text box, the search engine compares the keywords with its index, compiles a list of webpages for which the keywords are relevant, and arranges the list in a specific order. Each search engine uses its own unique software and formula or algorithm to determine the relevance of a webpage to specific keywords, and the order in which to rank or list the pages in the search results. • Most search engines attempt to present the most useful and relevant results or hits at or near the top of a search results list to make their search engines more useful and to attract more users. • Many search tools today have become hybrids — basing their results on indexes created both by web crawlers and by human editors.

  17. Search Tools – Metasearch Engines • A metasearch engine is a special type of search tool that compiles the search results from multiple search engines into a single search results list, effectively performing multiple different searches at once. Metasearch engines include Dogpile, Mamma.com, Zoo, and Ixquick. • When you enter search query keywords in a metasearch engine’s search text box, the metasearch engine submits the search query to a number of search engines at one time. It then compiles all of the results into a single list of hits. • A good metasearch engine should eliminate duplicate entries, categorize the hits based on topic, order the hits by relevance, and indicate which search engines provided the search results. • Metasearch engines typically rely heavily on sponsored listings, and some metasearch engines mix nonpaid and sponsored hits together in the same search results list; therefore, it is important that you carefully review the source of each hit returned by a metasearch engine to eliminate sponsored listings that might not be the most relevant to your search query.

  18. Advanced Search Techniques • Refining Searches using Boolean Operators. • A Boolean operator is a conjunction used in a logical expression. When given multiple keywords in a query, a search engine uses the AND, OR, and NOT (typed in all capital letters) Boolean operators to specify which keywords should be included in or excluded from the search results. • Be aware that not all search engines handle Boolean operators in the same way. You can review a search engine’s Help pages for tips on using Boolean operators in search queries.

  19. Boolean Operators Typical methods for formulating a search query using Boolean operator In addition to Boolean operators, major search engines also offer a number of searching shortcuts, such as the examples shown in Figure 3-27. See your search engine’s Help pages for more information about searching tips and shortcuts.

  20. Advanced Search Forms • Many search engines provide an advanced search form you can use to structure a complex search query. An advanced search form typically prompts you to specify Boolean operators and other criteria, such as filtering the results by language, file type, or domain (such as .gov or .edu). • Creating a complex search in an advanced search form is a great way to learn more about how to use specific search engine shortcuts and Boolean operators. As you fill in the form, the search engine creates the search query based on the form’s content, and then displays the completed search query at the top of the form and/or at the top of the search results page. You can review a completed search query to learn how to create similar searches by typing shortcuts and Boolean operators directly in the search engine’s search text box. • Try to use the Advanced Search Form on Page 114.

  21. Browser Searches • To search using the Address Box on the Address Bar. (See page 119) • To search a Webpage Using the Find Bar (Cntrl-f). (See page 121)

  22. Specialized Searches • People and Business Search: • One way to find webpages containing information about an individual or a business is to use the individual’s name or the company name as search keywords. • Looking for other information, such as an email address or telephone number, is more efficient when you use a specialized directory, such as an online white pages directory or yellow pages directory. Named for their similarity to telephone directories, white pages and yellow pages directories include free resources such as Pipl and Wink, and other directories, such as WhitePages and Superpages, that offer additional information for a fee (Figure 3-47).

  23. Specialized Searches (2) • News and Current Events Search: • Online news sources are diverse. Headlines often appear on the home pages of portal sites such as MSN and Yahoo!. • Websites for broadcast television and radio stations publish current news. Search engines such as Bing (Figure 3-49) enable you to search for news. • You can read the online version of various newspapers. Because most news is distributed through one of the major news wire services, such as the Associated Press (AP), United Press International (UPI), or Reuters, you will find the same or similar headlines and articles at various websites.

  24. Specialized Searches (3) • Video Search: • Some search engines, such as ClipBlast, and Yahoo! Screen (Figure 3-50), specialize in indexing websites that offer video clips. • Other search engines, such as Google, enable you to filter search results to show video or other specific media formats. • Social Media Search: • Another area of interest to Internet users is social media, which includes online tools used to communicate ideas, share links, contribute personal commentary, share photos, and interact online with other web users in various ways. • You can use specialized search engines, sometimes called social media aggregators, such as Technorati, Google Blog Search, Digg (Figure 3-51), and Newsvine, to locate social media resources.

  25. Specialized Searches (4) • Hashtag Search: • A hashtag is word or phrase (with spaces removed), preceded by the # sign. Hashtags are a form of metadata, and are used in social media platforms. Event promoters, politicians, social activists, entertainers, and more use hashtags to create and analyze trending topics. • Hashtags effectively create a group of related posts or media on a specific platform, such as Twitter. Twitter and other social media platforms track hashtag trends. Web services exist that enable you to search for hashtags, create and register a hashtag, and more. Tagboard, Talkwalker, Rite Tag, and Twubs (Figure 3-52) are examples of hashtag search engines and tools. • Shopping Search: • Shopping search engines, also known as shopping bots or shopping aggregators, include DealTime (Figure 3-55), Nextag, and Yahoo! Shopping. Shopping search engines aggregate, or collect, information about consumer products or services, and help online shoppers compare models, prices, shipping costs, and other variables from various sellers before they buy.

  26. Research Alternatives to Search Engines • For in-depth or scholarly research, a more effective strategy is to access specialized collections of electronic resources. • There are a few of the more powerful and well-known services, such as LexisNexis, Proquest (Figure 3-61), ingentaconnect, FindLaw, Dun & Bradstreet, and Hoover’s, which offer access to specialized information collections. • These services are usually available only through paid subscriptions because of the specialized and proprietary information they contain and/or the efforts that go into compiling, obtaining, and updating the information they include. • Many higher educational institutions subscribe to these services; therefore, students and faculty might have free access. If your school is not a subscriber, you still might be able to use these services through a public library that subscribes, by paying for an individual subscription, or with a pay-as-you-go fee.

  27. References • Discovering the Internet: Complete, Jennifer Campbell, Course Technology, Cengage Learning, 5th Edition-2015, ISBN 978-1-285-84540-1. • Basics of Web Design HTML5 & CSS3, Second Edition, by Terry Felke-Morris, Peason, ISBN 978-0-13-312891-8.

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