CHAPTER-3 HTML HTML is a markup language, which is used to define the layout and attributes of a World Wide Web (WWW) document as well as to create links between Web pages. HTML is the underlying foundation of Website design. It is a subset of SGML (Standard Generalised Markup Language) and a high-level markup language. HTML is a short form of HyperText Markup Language, which means (i) HyperText is simply a piece of text that has some extra features like formatting, images, multimedia and links to another document. (ii) Markup Language is a way of writing layout information within documents. HTML is a page layout and hyperlink specification language. It allows images and other objects to be embedded that can be used to create interactive forms. HTML documents are described through HTML tags or elements. HTML ELEMENTS or TAGS HTML is written in the form of tags. A tag refers to a string enclosed within angular brackets (< and >). HTML elements represent semantics or meaning. HTML tags are predefined and are not case-sensitive. All HTML tags are typed inside the angular brackets (< and >) and the text between these brackets are called elements. The opening tags are written within the less than (<) and greater than (>) signs, e.g. <HTML> The closing tags are written within the < and > signs with a forward slash (/) appended before the name of the tag. e.g. </HTML> The attributes are always specified in the opening tags, which provides additional information about that tag. It comes in name/value pairs like name = “value”, e.g. <FONT size =“5”> There are two kinds of elements, i.e. Container elements and Empty elements. Container Elements These types of HTML elements always wrap around the text or graphics which come in a set with an opening as well as a closing tag. In other words, HTML tags that include both On and Off tags are known as container tags. e.g. <HTML>.. .</HTML> Empty Elements On the other hand, the empty elements are standalone tags, i.e. empty tags do not have to be wrapped around text or graphics and do not require a closing tag. In other words, HTML tags that include only On tag and there is no Off tag then, these tags are known as empty tags. e.g. <HR> inserts a horizontal line <BR> adds a line break HTML STRUCTURE HTML document is a combination of various tags, which define the structure and appearance of the Web page. Following four basic structure elements are always present in every HTML document: (i) The <HTML> tag tells the browser that this is an HTML document. You must begin your html files with this tag and must end your html file with matching closing tag. (ii) The <HEAD> tag is used for text and tags that do not appear directly on the page. It acts as a header of file and contains some information like setting the title of the Web page. (iii) The <TITLE> tag contains the document title. This tag lies between <HEAD> and </HEAD> tags. The title specified inside this tag appears on the browser’s title bar. (iv) The <BODY> tag is used for text and tags that appears directly on the Web page. It helps us to create a look and feel of the Web page. It holds all your content words, pictures and other stuff. The most basic structure needed for creation of any Web page are as follows: CREATING and SAVING a HTML DOCUMENT Since, HTML documents are just text files, they can be written in any simple text editor like Notepad, FrontPage, Dreamweaver, WordPad etc. If you are using a Notepad to create a HTML document, the steps are as follows: Step 1: Open Notepad by clicking at Start —> All Programs —> Accessories —> Notepad. Step 2: Type the HTML document in Notepad as shown in the following figure: Step 3: To save the document, click at File menu —> Save As command. Step 4: The Save As dialog box will appear as shown in the following figure: Step 5: In Save As dialog box, after selecting the desired folder, give the desired file name along with the extension .htm or .html in the File name: box and then, click Save button. In the above figure, we have saved out HTML document under name First.html. VIEWING HTML DOCUMENT in a BROWSER You can view HTML document in any Web browser such as Internet Explorer, Mozilla Firefox, Opera, Apple Safari, Netscape Navigator, Google Chrome etc. Here, we are using Internet Explorer Web browser to view the HTML document. To view an HTML document, the steps are as follows: Step 1: Open Internet Explorer, by clicking at Start —> All Programs —> Internet Explorer. Step 2: To open the document First.html, select File menu —> Open. Step 3: The Open dialog box will appear as in the following figure: Step 4: Click the Browse… button, the Microsoft Internet Explorer dialog box will appear and select the file First as shown in the following figure: Step 5: Click Open button, and then click OK button. Step 6: Now, you will be viewing your desired page as shown in the following figure: BASIC HTML TAGS HTML provides some basic tags which are required for HTML code. <HTML>Tag It represents the root of an HTML document, so it acts as a container for all other HTML elements. It informs the browser that it is dealing with an HTML document. It is very important to place both of these tags (open and close HTML tags) in your documents as they tell the browser, where your page begins and ends, e.g. <HTML> </HTML> Attributes of <HTML> Tag This tag provides various attributes, which are as follows: DIR It tells the browser the direction in which the displayed text is to be read. This attribute can have values either ltr (left-to-right) or rtl (rightto-left). By default, the value of dir attribute is ltr. Syntax <HTML dir=“ltr"/“rtl”> LANG It specifies the language of an element content and attribute values. Now-a-days, Web pages are designed in many languages, e.g. German, Hindi, Greek, Spanish etc. Syntax <HTML lang=“fr”> Here, fr denotes to the French language. Some common language codes are as follows: Code Language Code Language en English hi Hindi fr French es Spanish de German ar Arabic it Italian ru Russian nl Dutch zh Chinese el Greek ja Japanese HEAD> Tag This element is a container for all the header elements. The <HEAD> tag must include a title for the document that can include scripts, styles, meta information and many more. The second line of your HTML document should be <HEAD>. The content contained in the head section of your document provides information to the browsers and search engines but, it is not displayed directly on the Web page. The end of the head tag is indicated by </HEAD>. e-g. <HTML> <HEAD> Header information comes here </HEAD> </HTML> <TITLE> Tag This tag defines the title of the document. Title must be a simple text and should not be same as the file name. It is placed between <HEAD> and </HEAD> tags. e-g<HTML> <HEAD> <TITLE> This is the title of my page. </TITLE> </HEAD> </HTML> output <BODY> Tag This tag defines the document’s body. It is used to set the basic page characteristics. It contains all the necessary contents of a HTML document, such as text, hyperlinks, images, tables, lists etc. The content of your Web page is placed in between the opening <BODY> and closing </BODY> tags. The <BODY> tag is opened just after the head section is closed. It is closed just before closing the <HTML> tag. e.g. <HTML> <HEAD> <TITLE> My First Web Page </TITLE> . </HEAD> <B0DY> Hello world. This is my first web page. </B0DY> </HTML> output Attributes of <BODY> Tag This tag provides various attributes, which are as follows: background This attribute specifies a background image for a document. HTML supports various graphics format such as .gif, .jpg etc. Syntax <B0DY background=“URL”> Where, URL may be an image name or a path of an image. e-g<HTML> <HEADXTITLE> Background Image </TITLEX/HEAD> <B0DY background ="image.jpg”> </B0DY> </HTML> Output Text This attribute specifies the color of the text in a document. Syntax <B0DY text=“color_name|hex_number|rgb_number”> Attribute Values e.g. <HTML> <B0DY text=“red”> Arihant Publication </B0DY> </HTML> Bgcolor This attribute specifies the background color of a document. Syntax <B0DY bgcol or=“color_name|hex_number|rgb_number”> e.g. <HTML> <B0DY bgcolor="red”> </B0DY> </HTML> Link This attribute specifies the color of an unvisited link in a document. The default color of link attribute is blue (#0000FF). Syntax <B0DY 1ink=“color_name|hex_number|rgb_number”> e.g. <HTML> <B0DY Iink=“red”> </B0DY> </HTML> Alink This attribute specifies the color of an active link in a document (a link get activated when it is clicked). The default color of an alink attribute is red (#FF0000). Syntax <B0DY alink=“color_name|hex_number|rgb_number”> e.g. <HTHL> <B0DY alink=“blue”> </B0DY> </HTML> Vlink This attribute specifies the color of a visited link in a document. The default color of vlink attribute is purple (#800080). Syntax <B0DY vl i nk=‘‘col or_name | hex_number | rgb_number”> e-g<HTML> <B0DY vlink=‘‘bl ue”> </B00Y> </HTHL> Topmargin Sets a topmargin (distance between the top of the document and the top of the browser window) of your body element. Syntax <B0DY topmargin=“value”> e.g. <HTML> <HEAD> <TITLE> Topmargin </TITLE> </HEAD> <B0DY topmargin=“65”> Arihant Publications is one such reputed name in the field of books which has the best available books in the market. </B0DY> </HTML> Output Leftmargin Sets a left hand margin (distance between the left side of the document and the left edge of the browser window) of your body element. Syntax <B0DY 1eftmargin=“value”> e.g. <HTML> <HEAD> <TITLE> Leftmargin </TITLE> </HEAD> <B0DY 1eftmargin=“65”> Arihant Publications is one such reputed name in the field of books which has the best available books in the market. </B0DY> </HTML> Output <FONT> Tag This tag specifies the font face, font size and font color of the text. The <FONT> tag provides no real functionality by itself but with the help of a few attributes, this tag is used to change style, size and color of HTML text elements. This tag is generally used for changing the appearance of a short segment of text. It can be set for a character, sentence or entire document. Attributes of <FONT> Tag Following are the attributes of <FONT> tag: size This attribute specifies the size of the text inside a <FONT> tag. The range of accepted values goes from 1 (the smallest) to 7 (the largest). We can also set the relative size to the current size using (+) ve or (-) ve sign, e.g. size = +2 Syntax <F0NT size=“number”> Attribute Value Value Description A number from 1 to 7, that defines the size of the text. Default number of number value is 3. e.g. <HTML> <HEAD> <TITLE> Font Size </TITLE> </HEAD> <B0DY> <F0NT size=“4”> This is the default size. </F0NT> </60DY> </HTML> Output face This attribute specifies the font name or type face of the text inside a <FONT> tag. Syntax <F0NT face=‘‘font_family”> Attribute Value Value Description The font name of the text specifies a prioritised list of several fonts, separate font_family the names with a comma (like <FONTface=“verdana,arial,sans-serif ”>. e.g. <HTML> <HEAD> <TITLE> Font Face </TITLE> </HEAD> <BODY> <FONT face=“verdana”> Thi s i s some text! </F0NT> </B0DY> </HTML> Output color This attribute specifies the color of the text inside a <FONT> tag. Syntax <FONT color=“color_name|hex_number|rgb_number”> e.g. <HTML> <B0DY> <F0NT cvolor=“red”> This is some text! </F0NT> </B0DY> </HTML> Some examples of using <FONT> tag are as follows: <F0NT size="3” color=“orange”> This is an example!</F0NT> <F0NT face=‘‘ari al ” col or=‘‘green”> This is a table!</F0NT> <F0NT size =+“2”> ABC </F0NT> <BASEFONT> Tag This tag specifies a default font color, font size or font family for all the text in a document that follows it, which is only supported by Internet Explorer Web browser. Ending tag (< /BASEFONT >) of basefont is optional. This tag can also have face, size and color attributes, which can be used exactly in the same way as face, size and color attributes of <FONT> tag. Attributes of < BASEFONT> Tag Following are the attributes of <BASEFONT> tag: color This attribute specifies the color of the text inside a <BASEFONT> tag. Syntax <BASEF0NT col or=‘‘color_name|hex_number|rgb_number”> face This attribute specifies the face type of the text inside a <BASEFONT> tag. Syntax <BASEF0NT face="font_family”> size This attribute specifies the size of the text inside a <BASEFONT> tag. Syntax <BASEFONT size=“number”> Differences between <F0NT> tag and <BASEF0NT> tag <FONT> tag <BASEFONT>tag The <BASEFONT> tag has optional “ending” The <FONT> tag has “ending” tag. tag. The <FONT> tag affects all text that lies The <BASEFONT> tag affects all text in a between its starting and ending tags. document. <CENTER> Tag This tag is used to centralise a segment of text to be displayed on browser’s window. With the <CENTER> tag, closing tag </CENTER> is always used. Anything between these two tags will be centered including text, images or tables. Syntax <CENTER> ... K/CENTER> e-g<HTML> <HEAD> <TITLE> Center </TITLE> . </HEAD> <B0DY> <CENTER> This text will be center-aligned. </CENTER> </B0DY> </HTHL> Output Comment <!-…- -> Tag This tag is used to insert comments in the source code of the Web page. Comments are not displayed in the browser’s window. All the text inserted inside this tag (<! — … — >) will be ignored by the browser that made invisible for the user. You can use comment to explain your code, it can help you, when you edit the source code later. This is especially useful, when you have a lot of codes. Syntax <! - -.... - -> <HTML> <HEAD> <TITLE> Comment </TITLE> </HEAD> <B0DY> <!- - This is a comment. - - > This is body. </BODY> </HTML> Output Heading Tags In HTML, heading tags are used to display the text as a heading. It can also be used to give section headings. There are six levels of headings, ranging from <H1>…</H1> to <H6>…</H6>. <H1> defines the most important largest heading level. <H6> defines the smallest heading level. Syntax <Hn>...........</H n> Where, n may be any number from 1 to 6. e-g<HTML> <HEAD> <TITLE> Heading Level </TITLE> </HEAD> <B0DY> <H1> level 1 Head!ine </H1> <H2> level 2 Headline </H2> <H3> level 3 Headline </H3> <H4> level 4 Headline </H4> <H5> level 5 Headline </H5> <H6> level 6 Headline </H6> Output Attribute of <HEADING> Tag Following is the attribute of <HEADING> tag: align This attribute specifies the alignment of the text as heading. By default, alignment is left. Syntax <Hn a 1 i gn=“center 11 eft | right | justify”X/H/?> Where, n=l to 6 e-g<HTML> <HEAD> <TITLE> Heading in HTML </TITLE> </HEAD> <B0DY> <H1 align = “center”>level 1 Headl ine</Hl> <H2> level 2 Headline </H2> <H3 align = “right”> level 3 Headline </H3> <H4> level 4 Headline </H4> <H5 al i gn = "center”> 1 evel 5 Headline </H5> <H6> level 6 Headline </H6> </B0DY> </HTML> Output Paragraph <P> Tag This tag is used to mark a block of text as a paragraph. It is used to insert a line break with extra space in the beginning. This is a container tag. Syntax <P>.........</P> e.g. <HTML>, <HEAD> <TITLE> Paragraph </TITLE> </HEAD> <B0DY> <P>This is some text in a paragraph.</P> </B0DY> </HTML> Output Attribute of <P> Tag Following is the attribute of <P> tag: align This attribute specifies the alignment of the text within a paragraph. By default, alignment is left. Syntax <P a 1ign="left|right|center|justify”> e.g. <HTML> <HEAD> <TITLE> P tag with align attribute </TITLE> </HEAD> <B0DY> <P align="right”> This is some text in a paragraph. </P> </B0DY> </HTML> Output Line Break <BR> Tag This tag is used to insert a line break which means the text/image following the tag will be moved to the next line when displayed in the browser. To add a single line of space, you can use a break tag <BR>. This is an empty tag, i.e. no need of closing tag. You can also use the <BR> tag to insert one or more blank lines. e-g. <HTML> <HEAD> <TITLE> Line BreaK </TITLE> </HEAD> <B0DY> This text contains <BR> a line break. </B0DY> </HTML> Output Horizontal Rule <HR> Tag To create a horizontal line on your page, you have to use the empty tag <HR>. This horizontal line can be used to divide information into sections. Attributes of <HR> Tag Following are the attributes of <HR> tag: align This attribute specifies the alignment of a horizontal line. Syntax <HR align=“left|center|right”> e.g. <HTML> <HEAD> <TITLE> HR tag with align attribute </TlTLE> </HEAD> <B0DY> <HR align=“right”> This is a line. </B0DY> </HTML> Output size This attribute specifies the height of the rule in pixels. A pixel is a tiny dot that makes up the display of your computer. Its default value depends directly on the browser. The default size of a rule is 3 pixels. Syntax <HR size="pixels”> Attribute Value Value Description The height of the <HR> tag in Pixels pixels. e.g. <HTML> <HEAD> <TITLE> HR tag with size attribute </TITLE> </HEAD> <B0DY> <HR size=“3”> This is a line. </B0DY> </HTML> Output
