HTML.ppt
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The Web and HTML Tutorial Building a Webpage Chapter Overview The World Wide Web – Web servers, Web browsers and Web pages HTML Introduction Using HTML Tags Moving to XHTML General Webpage Structure Designing with Standards UB Web Environment Web Pages Viewing a web page involves using a web browser (IE, Firefox, Mozilla) to connect to a networked machine running web server software (IIS, Apache). This action loads an HTML file from the web server and sends it to your computer across the Internet using the HTTP and TCP/IP protocols, and the file is displayed by your web browser software as a web page. Web Server Stats Useful Web Stats www.w3schools.com/browsers gs.statcounter.com – OS – Browsers – Display Resolution W3C Founded in 1994 – World Wide Web Consortium Creates specifications and guidelines that are intended to promote the web’s evolution and ensure that web technologies work well together Specifications for: HTML, CSS, XML, XHTML, DOM, etc… W3C Not all browser companies follow or adhere to these guidelines – It was not until FireFox, Netscape 7 and IE 6 did browsers truly support the W3C Web Standards Web pages may look different in two browsers – Browsers support different standards, not all of them and support them in different methods HTML Introduction HTML (Hypertext Markup Language) is the code used to build web pages. Web pages are text files with HTML code. You can view the HTML code on any webpage by clicking on Source from the View menu in a web browser. HTML files usually have either .htm or .html file extension Default Web pages Default page appears when visiting a website without specifying the file name in the URL. – www.cnn.com displays www.cnn.com/index.html Default pages are usually either index.htm, index.html, index.asp, index.cfm, default.htm, default.html, default.asp or default.cfm. These options are configured in the web server. Using HTML Tags Most HTML tags have an opening and corresponding closing tag indicated by a slash /. – <pre>…</pre> – <b>…</b> Anything between the tags, denoted by the “…” in the above examples, will be modified according to the behavior described by the tag *All XHTML tags should be closed HTML Caveats Extra spaces (beyond one) in the code and any line breaks are ignored by the browser when rendering the HTML page. &nbsp; is a special symbol that can be used to insert extra spaces. <br> or <p> can be used to create necessary line breaks. HTML Caveats HTML Caveats Moving to XHTML XHTML (Extensible Hypertext Markup Language) is a hybrid of HTML and XML and should be used to code websites to meet the latest standards set by W3C. – All tags must be closed - including tags like <br /> – All tags should be in lowercase except for the DOCTYPE tag. – All tag attributes must be quoted and have values – CSS are used for page formatting. General Webpage Structure <!DOCTYPE html PUBLIC etc…> <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"> <head> <title> … </title> </head> <body> … </body> </html> DOCTYPE Options DOCTYPE – 3 types to choose from Transitional – more easy going and flexible. Most people are using this Strict – everything must be perfect and there is no flexibility. Frameset – Allows you to use frames on your page Designing with Standards Does not mean “designing for the latest browsers only” Includes structural languages like XHTML and XML and presentation languages like CSS Even the perfectly designed site will never look identical in all browsers but it should always function and look very similar in any browser Designing with Standards Lowers production and maintenance costs Makes sites more accessible to users who have special needs Makes sites cross platform and browser – PDAs, Cell phone browsers, IE, Mozilla, Netscape, Opera Screen Readers Viewable on handheld devices Designing with Standards Structure: When authored correctly XHTML will work in all web browsers, screen readers, text browsers, and handheld devices Valid/Semantic Code when: – – – Contains no errors Tags are chosen according what they mean- eg – h1-> headline Code can be valid but not semantic Designing with Standards Structure: A markup language (XHTML) contains text data formatted according to its structural (semantic) meaning. – Headline, paragraph, list etc.. Example: <p>this is a paragraph of text</p> <h1>News & Events</h1> <ul> <li>structure</li> <li>presentation</li> <li>behavior</li> </ul> Designing with Standards Presentation languages (CSS) format the web page, controlling the typography, placement, color, etc… Due to the separation of structure from presentation you can easily change one without affecting the other CSS is implemented with inline, internal or external style sheets Large sites may be able to reduce bandwidth costs too Cleaner code with CSS WITHOUT CSS <p><font color=“#000000” size=“10px”><b>heading of an article</b></font></p> WITH CSS <p class=“articleheading”>heading of an article</p> Accessibility Intended to ensure that our work will be usable and available to the largest possible number of people Hot topic in the web design industry Laws are in place to make sure companies and web designers adhere to certain rules Who does it affect? Visually impaired – blind or limited site or elderly Physically disabled Color blind Motor impaired – rather buy online than deal w/the hassle of going to a store Any thoughts on who else? There are a whole bunch more! Who does it affect? Search engine crawlers – extreme blind user – – Called the “Blind Billionaire” Biggest category of blind users PDA users Text only browsers Cell Phone users UB Web Environment UB provides web space for each student on the UBUNIX servers which run the Apache webserver. Your webpage can be viewed in any of the 3 locations. – www.buffalo.edu/~djmurray – www.acsu.buffalo.edu/~djmurray – wings.buffalo.edu/~djmurray UB Web Environment URLs and files are case sensitive because the UNIX OS is case sensitive. – www.buffalo.edu/~djmurray/INDEX.html - error! – www.buffalo.edu/~djmurray/index.html - works! Windows servers running IIS are not case sensitive. – www.ubathletics.buffalo.edu/INDEX.html - works! – www.ubathletics.buffalo.edu/index.html - works! UB Web Environment Remember that a webpage is simply a file stored on a webserver in a particular location. Your UB homepage is stored in the public_html directory of your S: drive. Anything in that directory is technically on the web. UB Web Environment It’s easiest to work from a lab computer since they have direct access to the S: drive folders. Enable your homepage first. – https://ubfs.buffalo.edu/cgi-bin/ubfs_activatepersonalwebsite.cgi Use Windows Notepad to edit the index.html file in your public_html folder. UB Web Environment If you are using a computer on the UB network (Resnet, wireless, VPN), you can map a network drive and create your own S: drive as explained at this website. http://ubit.buffalo.edu/ubfs/accessubfs.php UB Web Environment Another option is using FTP software (Filezilla or Fetch) to upload files to your UB web space using these settings. VPN also required when using from off campus. Host: ubunix.buffalo.edu Server Type: SFTP – SSH File Transfer Protocol Login Type: Ask for password Next Steps… The hard part is often understanding how the web environment works and where to save the HTML files so they appear on the web! Now its time to try some HTML tags.
