Chapter 8 Browsing and Searching the Web
Getting Started • In this Chapter, you will learn: − What is a Web page − What is a URL − How a browser works − How to use a search engine − About saving text and graphics that are found on the Web − About Hardware: Web servers Practical PC 5 th Edition Chapter 8 2
What’s a Web page? • A Web page is the output of Web-based files which is then displayed on your computer – Millions of Web pages are available on the Web – Clickable hypertext links allow you to move between Web pages • Computers that store Web pages are known as Web servers – Each Web server hosts one or more Web sites – Web sites contain information about a specific topic – The person who creates and maintains a site is the Webmaster Practical PC 5 th Edition Chapter 8 3
What’s a Web page? • The main page of a Web site is the home page – Any page on a Web site can be linked to the home page or to other Web pages – Text links usually appear as blue or green underlined words – Graphics links appear as pictures – When you point to a link the pointer changes to a hand-shaped link pointer – By clicking a link you are requesting the Web page indicated by the link Practical PC 5 th Edition Chapter 8 4
What’s a Web page? Web page with text and graphic links Practical PC 5 th Edition Chapter 8 5
What’s a URL? • A URL (uniform resource locator) is a Web page address – Most URLs begin with HTTP (Hypertext Transfer Protocol) indicating the communication standard – The Web server’s name begins with www, the name of the company, and the top-level domain, such as. com or. gov – A folder name, file name, and file extension, may follow like this: /contest/rules. htm – Most Web pages have an. htm or. html extension because they are stored in a file format used on the Web called HTML (Hypertext Markup Language) Practical PC 5 th Edition Chapter 8 6
What’s a URL? Example of a URL Practical PC 5 th Edition Chapter 8 7
How does a browser work? • A Web browser is the software that displays Web pages on your computer screen. The browser: – Interprets HTML tags embedded in the file – Handles links between Web pages • Plug-ins are programs that extend the variety of files and media that your browser can display, such as Adobe Flash Player • Your browser can interact with a Web server to create a cookie, which is a message that contains information to help the Web server identify you the next time you visit the Web site Practical PC 5 th Edition Chapter 8 8
How does a browser work? Browser Practical PC 5 th Edition Chapter 8 9
How do I use a search engine? • A search engine catalogs Web pages to make it easier to find information – Popular search engines are Google and Yahoo! – You enter words and phrases in the Search box and the search engine returns a list of links to pages that match your search criteria • Most search engines can handle simple and complex searches – A simple search would be entering in a topic and a few synonyms such as “weight loss diet calories” – A complex search would return a more targeted list by using sophisticated search techniques. Consult your search engine’s online Help for these techniques Practical PC 5 th Edition Chapter 8 10
How do I use a search engine? Search Engine Practical PC 5 th Edition Chapter 8 11
Can I save text and graphics that I find on the Web? • You can print or save articles and graphics – To print a Web page, use your browser’s Print button or the Print option on the File menu – You can also save a copy of the entire Web page, selected paragraphs, or graphics • Respect the Author’s intellectual property rights – If you want to use a graphic that you downloaded, you should obtain permission by e-mailing the copyright holder – If you incorporate text into your documents you must include a citation with the author’s information Practical PC 5 th Edition Chapter 8 12
Hardware: Web servers • Web sites, blogs and e-commerce sites are handled by Web servers that run specialized software − A blog is a Web site that is formatted as a series of journal entries − An e-commerce site offers online access to merchants and services to buy − Internet service for a Web server is typically more expensive than standard service − Web servers require constant attention and need to be operational around the clock Practical PC 5 th Edition Chapter 8 13
Hardware: Web servers • Most people host their Web site with a Web hosting service, which is a company that operates industrial-strength servers − Web page hosting offers space for personal Web pages − Blog hosting offers software for creating blogs − Image hosting and video hosting offers sites where you can upload photos or video clips − E-commerce hosting offers software and server space to construct an online store Practical PC 5 th Edition Chapter 8 14
Hardware: Web servers • The financial model for Web hosting varies − Sites that host personal Web pages are sometimes free, especially if visitors have to view ads − Many hosting services charge a nominal monthly fee in exchange for upgraded storage space, number of simultaneous connections, or amount of data transferred − E-commerce hosting is usually fee-based • Anyone can obtain a domain name from an authorized domain name registrar Practical PC 5 th Edition Chapter 8 15
Hardware: Web servers Blade (or rack-mounted) Server Practical PC 5 th Edition Chapter 8 16
Hardware: Web servers Registering a Domain Name Practical PC 5 th Edition Chapter 8 17
The filtering controversy • What do you think? – If you had children, would you use filtering software on your home PC to block access to certain Web sites? – Do you think schools and public libraries that provide Internet access to children should use filtering software? – Should a government prevent its citizens from accessing Web-based material that does not conform with its political and cultural agenda? Practical PC 5 th Edition Chapter 8 18
Chapter Summary • You should now know: − What is a Web page − What is a URL − How a browser works − How to use a search engine − How to save text and graphics that are found on the Web − About Web servers Practical PC 5 th Edition Chapter 8 19
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