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  1. THE INTERNET • Concept started in late 1950s, but important since 1992 • Designed for the U.S. military • Series of interconnected sites from many areas • Designed to withstand losses of large portions • Now international • Actual computers and cables • Number of host computers - not web pages or sites • 1969 = 4 • 1997 = 20 million • 2002 = 200 million • The Internet Society

  2. THE INTERNET • Two systems now • Internet1 • The commodity internet • • Internet2 • Led by more than 200 U.S. universities, working with industry and government, Internet2 develops and deploys advanced network applications and technologies for research and higher education, accelerating the creation of tomorrow's Internet • • One of the advantages Internet2 has over the existing Internet is speed. The network will never be available to the public, though, as it's solely a research tool. •,1895,1843288,00.asp

  3. WORLD WIDE WEB • Most used part of the Internet • Actually the information • Made the internet useful • Accessed with a browser

  4. UniformResourceLocator • The global address of documents and other resources on the World Wide Web • The first part of the address indicates what protocol to use • The second part specifies the IP address or the domain name where the resource is located. • For example, the two URLs below point to two different files at the domain • •

  5. File Transfer Protocol • FTP, the protocol used on the Internet for exchanging files. • Connects to a file server. • Entire files are transferred from one device to another and copied into memory • FTP is most commonly used to download a file from a server using the Internet or to upload a file to a server (e.g., uploading a Web page file to a server). • FTP works in the same way as HTTP for transferring Web pages from a server to a user's browser and SMTP for transferring electronic mail across the Internet

  6. Hyper Text Transfer Protocol • HTTP • Used to transfer files from a Web server onto a browser in order to view a Web page that is on the Internet. • HTTP is a one-way system onto the workstation. Connects to a Web server and not a file server. • Secure Sockets Layer (SSL) transmits secure communications. SSL is designed to establish a secure connection between two computers, S-HTTP (another protocol) is designed to send individual messages securely. • By convention, URLs that require an SSL connection start with https: instead of http:.

  7. IP ADDRESSES • Every computer using the Internet is assigned an IP address • uniquely identifies the device • distinguishes it from other computers • Dynamic Host Configuration Protocol (DHCP) – UW uses • Assigns IP addresses centrally and changes when computer is moved to new connection. • Domain Name System (or Service) is an Internet service that translates domain names into IP addresses. • Domain names being alphabetic are easier to remember. • The Internet, however, is really based on IP addresses. • For example, the domain name might translate to • The DNS system is its own network. If one DNS server doesn't know a particular domain name, it asks another one


  9. SEARCHING THEINTERNET • PORTALS • Offer search, directory, and many other general services such as email, home page building, news, and popular topics • Yahoo!, Excite, AOL, Inktomi, MSN, and Lycos. • WyoWeb [] • Search engines often add portal services • SUBJECT DIRECTORY • includes selected Web sites (more often than pages) and classifies them into hierarchical subject categories. • Britannica • LookSmart • The Open Directory (Dmoz) • Yahoo!

  10. MEDHUNT • MedHunt is a medical and health search engine • MARVIN, a Web-spider, was first applied to the medical domain. Armed with a dictionary of medical terms, MARVIN tirelessly skims the Web for new sources of medical information. MARVIN feeds and constantly updates MedHunt. • MARVIN and MedHunt have been developed by HON.

  11. SEARCH ENGINES • PRIMARY SEARCH ENGINES (as of April 2004) • Google • MSN Search • Teoma [basis of Ask Jeeves] • Yahoo! • Gigablast (minor player) • OTHERS • Either using one of the above or no longer exist • Search aggregators like • combine results from other search engines • G. Notess, •

  12. Dogpile report;; 2005

  13. ADDRESS EXTENSIONS • .COM = Commercial • .NET = network (often personal sites), administrative • .ORG = organization • .GOV = government • .MIL = military • .EDU = educational (often student sites); also .AC • .FIRM = business • .INT = international institutions • .NOM = personal sites • .STORE = store • .WEB = sites about the web •

  14. ADDRESS EXTENSIONS • Country designations • .ca = Canada • .de = Germany • .uk = United Kingdom •

  15. USE OF THE INTERNET • Health Professionals use the Internet for medical information at work • daily 68.19 % • at least once a week 10.55 % • at least once a month 1.64 % • less than once a month 6.58 • Never 13.04% • Health on the Internet Foundation •, May-July 2002

  16. USE OF THE INTERNET • Health Professionals use the Internet for medical information at home • daily 72.82 % • at least once a week 17.46 % • at least once a month 1.57 % • less than once a month 5.01 % • Never 3.14% • Health on the Internet Foundation •, May-July 2002

  17. USE OF THE INTERNET • The 80 metropolitan markets with 130.4 million adults. 79.9 million log on regularly. • 61.2 % of all adults visit the Internet regularly. • 56.7 of 55 to 64 year olds • 35.9% of 65 to 74 year olds • 15.9% of those age 75 plus • 55.6% of married, age 35 plus, households without children access the computer regularly while 65.1% of households with children do • Households with annual incomes of $50,000 or more the Internet access rate is 78.6 percent. • December  17, 2004- The Media Audit (International Demographics, Inc.,

  18. JAMA, 2003;289:2400-2406


  20. HONCode • The Health On the Net Foundation (HON) • Created in 1995 • A not-for-profit International Swiss Organization • HON's mission is to guide lay persons or non-medical users and medical practitioners to useful and reliable online medical and health information. • HON provides leadership in setting ethical standards for Web site developers. •

  21. IS A SITE FEATURING THE SEAL BONA FIDE? • 1. Place the cursor over the featured HONcode seal • an ID number will appear along the bottom of the on-screen frame. • 2. Click on the HONcode seal. • links to a page on HON's site summarizing the site's status. • If not, the site is not HONcode compliant. • 3. Can also use HON's own Site Checker. • HON's MedHunt search engine will display results instantaneously. • Note: The fact that a given Web site does not bear the HONcode seal and is not listed on HON's MedHunt is NOT necessarily an indication of poor quality. • e.g.

  22. HONcode PRINCIPLES • 1. AUTHORITY • Any medical or health advice is only given by medically trained and qualified professionals unless a clear statement is made that the advice offered is from a non-medically qualified individual or organization. • 2. COMPLEMENTARITY • The information provided on this site is designed to support, not replace, the relationship that exists between a patient/site visitor and his/her existing physician. • 3. CONFIDENTIALITY • Confidentiality of data relating to individual patients and visitors to a medical/health Web site, including their identity, is respected by this Web site.

  23. HONcode PRINCIPLES • 4. ATTRIBUTION • Where appropriate, information contained on this site will be supported by clear references to source data and, where possible, have specific HTML links to that data. The date when a clinical page was last modified will be clearly displayed • 5. JUSTIFIABILITY • Any claims relating to the benefits/performance of a specific treatment, commercial product or service will be supported by appropriate, balanced evidence in the manner outlined above • 6. TRANSPARENCY OF AUTHORSHIP • The designers of this Web site will seek to provide information in the clearest possible manner and provide contact addresses for visitors that seek further information or support. The Webmaster will display his/her E-mail address clearly throughout the Web site.

  24. HONcode PRINCIPLES • 7. TRANSPARENCY OF SPONSORSHIP • Support for this Web site will be clearly identified, including the identities of commercial and non-commercial organizations that have contributed funding, services or material for the site. • 8. HONESTY IN ADVERTISING & EDITORIAL POLICY • If advertising is a source of funding it will be clearly stated. A brief description of the advertising policy will be displayed on the site. Advertising and other promotional material will be presented to viewers in a manner and context that facilitates differentiation between it and the original material.

  25. EVALUATING WEB SITES • Look for all of the factors used for the HonCode • Currency – is the date displayed? • Ease of use • Loads in a reasonable amount of time • Understandability • AS WITH LITERATURE, NO PERFECT SITE

  26. PROPER CITATION • Author name (if given). Title of page (e.g. drug name) [mongraph online]. Title of Site. Date of monograph/site [cited Year Month Day (when you looked at it; e.g. 2000 Jun 5)];[number of screens (for the specific section –e.g.your drug) ]. Available from: URL:

  27. WHEN TO USE THE INTERNET • To access tertiary, secondary, or primary references • If have a web address as a part of the question • Company-specific information • Package inserts • Current news • Government information • Software-related needs • When information is unlikely to be available elsewhere • Alternative therapies, for example