1. ITIS 1210 Introduction to Web-Based Information Systems Chapter 27 How Internet Searching Works

2. Introduction  Too many people think Google is the Internet  It’s their default search engine  Still, relatively new:  Founded in 1998  Became largest search engine in 2000  How did it become so popular in such a short period of time?

3. Introduction  Primarily because it was better at what it did than other sites  Marketing only gets you so far  Ultimately your site has to perform  How? Algorithms  Series of well-defined steps to accomplish an objective

4. Introduction  What pages are relevant to your search?  Where is the search term found within the page?  How popular is the page?  Who links to that page?  Are those links from well-regarded sites?  If so, the relevance of the page increases

5. Introduction  Originally a search engine  Now much more  Froogle – a buying service  Gmail – Email  Maps  Readers

6. How Google Searches the Internet  When you use Google search  Actually searching a large index  How is this index created and maintained?  Googlebots  Web-crawling robot  Sends a request to a Web server  Downloads the page

7. How Google Searches the Internet  Googlebots take up bandwidth  Problem because it limits legitimate user interactions  Google provides tools that allow Webmasters to throttle-down the crawl rate

8. How Google Searches the Internet  All links in page added to a queue  Those links eventually crawled  “Deep crawling”

9. How Google Searches the Internet

13. What Google Knows About You  Google tracks what you search  After 500 searches, can Google make any determinations about who you are and what interests you?  Are you political?  Are you constantly looking for entertainment Web sites?  Can you spell?

14. What Google Knows About You  To date, Google may not keep track of all this information  But it could  Sell your info to the highest bidder?  A government  Your insurance company