ch5.pdf

JTO Ph-II DNIT HTML CSS CHAPTER 5 : MARKUP LANGUAGE – HTML AND CSS 5.1 Learning Objective  HTML stands for Hyper Text Markup Language  An HTML file is a text file containing small markup tags  The markup tags tell the...

JTO Ph-II DNIT HTML CSS CHAPTER 5 : MARKUP LANGUAGE – HTML AND CSS 5.1 Learning Objective  HTML stands for Hyper Text Markup Language  An HTML file is a text file containing small markup tags  The markup tags tell the Web browser how to display the page  An HTML file must have an htm or html file extension  An HTML file can be created using a simple text editor 5.2 Prepare a very simple html page If you are running Windows, start Notepad. Type in the following text: Title of page This is my first homepage. This text is bold  Save the file as "mypage.htm". Start your Internet browser. Select "Open" (or "Open Page") in the File menu of your browser. A dialog box will appear. Select "Browse" (or "Choose File") and locate the HTML file you just created - "mypage.htm" - select it and click "Open". Now you should see an address in the dialog box, for example "C:\MyDocuments\mypage.htm". Click OK, and the browser will display the page. EXAMPLE EXPLAINED The first tag in your HTML document is. This tag tells your browser that this is the start of an HTML document. The last tag in your document is. This tag tells your browser that this is the end of the HTML document. The text between the tag and the tag is header information. Header information is not displayed in the browser window. The text between the tags is the title of your document. The title is displayed in your browser's caption. The text between the tags is the text that will be displayed in your browser. JTO PH-II IT Version Page 56 of 131 For Restricted Circulation  JTO Ph-II DNIT HTML CSS The text between the and tags will be displayed in a bold font. 5.3HTM or HTML Extension? When you save an HTML file, you can use either the.htm or the.html extension. We have used.htm in our examples. It might be a bad habit inherited from the past when some of the commonly used software only allowed three letter extensions.With newer software we think it will be perfectly safe to use.html. 5.4Note on HTML Editors: You can easily edit HTML files using a WYSIWYG (what you see is what you get) editor like FrontPage, Claris Home Page, or Adobe PageMill instead of writing your markup tags in a plain text file. But if you want to be a skillful Web developer, we strongly recommend that you use a plain text editor to learn your primer HTML.HTML documents are text files made up of HTML elements.HTML elements are defined using HTML tags. 5.5HTML Tags  HTML tags are used to mark-up HTML elements  HTML tags are surrounded by the two characters < and >  The surrounding characters are called angle brackets  HTML tags normally come in pairs like and  The first tag in a pair is the start tag, the second tag is the end tag  The text between the start and end tags is the element content  HTML tags are not case sensitive, means the same as 5.6HTML Elements Remember the HTML example from the previous page: Title of page This is my first homepage. This text is bold This is an HTML element: JTO PH-II IT Version Page 57 of 131 For Restricted Circulation  JTO Ph-II DNIT HTML CSS This text is bold The HTML element starts with a start tag: The content of the HTML element is: This text is bold The HTML element ends with an end tag: The purpose of the tag is to define an HTML element that should be displayed as bold. This is also an HTML element: This is my first homepage. This text is bold This HTML element starts with the start tag , and ends with the end tag. The purpose of the tag is to define the HTML element that contains the body of the HTML document. Why do We Use Lowercase Tags? We have just said that HTML tags are not case sensitive: means the same as. When you surf the Web, you will notice that most tutorials use uppercase HTML tags in their examples. We always use lowercase tags. Why? If you want to prepare yourself for the next generations of HTML, you should start using lowercase tags. The World Wide Web Consortium (W3C) recommends lowercase tags in their HTML 4 recommendation, and XHTML (the next generation HTML) demands lowercase tags. Tag Attributes Tags can have attributes. Attributes can provide additional information about the HTML elements on your page. This tag defines the body element of your HTML page:. With an added bgcolor attribute, you can tell the browser that the background color of your page should be red, like this:. This tag defines an HTML table:. With an added border attribute, you can tell the browser that the table should have no borders: Attributes always come in name/value pairs like this: name="value". JTO PH-II IT Version Page 58 of 131 For Restricted Circulation  JTO Ph-II DNIT HTML CSS Attributes are always added to the start tag of an HTML element. QUOTE STYLES, "RED" OR 'RED'? Attribute values should always be enclosed in quotes. Double style quotes are the most common, but single style quotes are also allowed. In some rare situations, like when the attribute value itself contains quotes, it is necessary to use single quotes: name='John "ShotGun" Nelson' The most important tags in HTML are tags that define headings, paragraphs and line breaks. The best way to learn HTML is to work with examples. We have created a very nice HTML editor for you. With this editor, you can edit the HTML source code if you like, and click on a test button to view the result. Headings Headings are defined with the to tags. defines the largest heading. defines the smallest heading. This is a heading This is a heading This is a heading This is a heading This is a heading This is a heading HTML automatically adds an extra blank line before and after a heading. Paragraphs Paragraphs are defined with the tag. This is a paragraph This is another paragraph HTML automatically adds an extra blank line before and after a paragraph. Line Breaks JTO PH-II IT Version Page 59 of 131 For Restricted Circulation  JTO Ph-II DNIT HTML CSS The tag is used when you want to end a line, but don't want to start a new paragraph. The tag forces a line break wherever you place it. This is a paragraph with line breaks The tag is an empty tag. It has no closing tag. Comments in HTML The comment tag is used to insert a comment in the HTML source code. A comment will be ignored by the browser. You can use comments to explain your code, which can help you when you edit the source code at a later date. Note that you need an exclamation point after the opening bracket, but not before the closing bracket. Basic Notes - Useful Tips When you write HTML text, you can never be sure how the text is displayed in another browser. Some people have large computer displays, some have small. The text will be reformatted every time the user resizes his window. Never try to format the text in your editor by adding empty lines and spaces to the text. HTML will truncate the spaces in your text. Any number of spaces count as one. Some extra information: In HTML a new line counts as one space. Using empty paragraphs to insert blank lines is a bad habit. Use the tag instead. (But don't use the tag to create lists. Wait until you have learned about HTML lists.) You might have noticed that paragraphs can be written without the closing tag. Don't rely on it. The next version of HTML will not allow you to skip ANY closing tags. HTML automatically adds an extra blank line before and after some elements, like before and after a paragraph, and before and after a heading. We use a horizontal rule (the tag), to separate the sections in our tutorials. Basic HTML Tags Description Tag Defines an HTML document JTO PH-II IT Version Page 60 of 131 For Restricted Circulation  JTO Ph-II DNIT HTML CSS Defines the document's body to Defines header 1 to header 6 Defines a paragraph Inserts a single line break Defines a horizontal rule Defines a comment 5.7How to View HTML Source Have you ever seen a Web page and wondered "Hey! How did do they do that?" To find out, click the VIEW option in your browser's toolbar and select SOURCE or PAGE SOURCE. This will open a window that shows you the HTML code of the page. Text Formatting Tags Tag Description Defines bold text Defines big text Defines emphasized text Defines italic text Defines small text Defines strong text Defines subscripted text Defines superscripted text Defines inserted text Defines deleted text Deprecated. Use instead Deprecated. Use instead Deprecated. Use styles instead "Computer Output" Tags Tag Description Defines computer code text Defines keyboard text Defines sample computer code Defines teletype text Defines a variable JTO PH-II IT Version Page 61 of 131 For Restricted Circulation  JTO Ph-II DNIT HTML CSS Defines preformatted text Deprecated. Use instead Deprecated. Use instead Deprecated. Use instead Citations, Quotations, and Definition Tags Tag Description Defines an abbreviation Defines an acronym Defines an address element Defines the text direction Defines a short quotation Defines a citation Defines a definition term Some characters like the < character, have a special meaning in HTML, and therefore cannot be used in the text. To display a less than sign (