BASICS OF <HTML>

Ranveer Aggarwal

Department of Computer Science and Engineering

IIT Bombay

Hello world!

Welcome to HTML Basics. This workshop leads you through the basics of Hyper Text Markup Language

(HTML). HTML is the building block for web pages. You will learn to use HTML to author an HTML page

to display in a web browser.

PS: These slides, to some extent, are made in HTML.

objectives

By the end of this workshop, you will be able to:

Use a text editor to author an HTML document.
Be able to use basic tags to denote paragraphs, emphasis or special type.
Create hyperlinks to other documents.
Create an email link.
Add images to your document.
Use a table for layout.
Apply colors to your HTML document.

prerequisites

Enthu
Creativity
A text editor like Notepad, Notepad++, Sublime Text etc. with Sublime Text being the most preferable.
A web browser like Google Chrome, Mozilla Firefox, Internet Explorer etc.

What is an html File?

HTML is a format that tells a computer how to display a web page. The documents themselves are plain text files with special "tags" or codes that a web browser uses to interpret and display information on your computer screen.

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

Try It?

Open your text editor and type the following text:

<html> 
<head> 
<title>My First Webpage</title> 
</head> 
<body> 
This is my first homepage. <b>This text is bold</b> 
</body> 
</html>

try it?

Now you would like to see how the browser interprets your code. So, just save the file as mypage.html. Now go to the file directory and right-click on the file and click on Open With > Google Chrome (or any other web browser).

To view how the page should look, visit this web page:

www.cse.iitb.ac.in/~ranveer/tutorials/html/mypage.html

example explained

What you just made is a skeleton html document. This is the minimum required information for a web document and all web documents should contain these basic components. The first tag in your html document is <html>. This tag tells your browser that this is the start of an html document. The last tag in your document is </html>. This tag tells your browser that this is the end of the html document.

example explained

The text between the <head> tag and the </head> tag is header information. Header information is not displayed in the browser window.

The text between the <title> tags is the title of your document. The <title> tag is used to uniquely identify each document and is also displayed in the title bar of the browser window.

The text between the <body> tags is the text that will be displayed in your browser.

The text between the and tags will be displayed in a bold font.

HTM or html

When you save an HTML file, you can use either the .htm or the .html extension. The .htm extension

comes from the past when some of the commonly used software only allowed three letter extensions.

It is perfectly safe to use either .html or .htm, but be consistent. mypage.htm and mypage.html are

treated as different files by the browser.

how to view html source

A good way to learn HTML is to look at how other people have coded their html pages. To find out,

simply click on the View option in your browsers toolbar and select Source or Page Source. This will

open a window that shows you the actual HTML of the page. Go ahead and view the source html for

this page.

html tags

what are html 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

Logical v/s Physical Tags

In HTML there are both logical tags and physical tags. Logical tags are designed to describe (to the

browser) the enclosed text's meaning. An example of a logical tag is the tag. By

placing text in between these tags you are telling the browser that the text has some greater

importance. By default all browsers make the text appear bold when in between the and

tags.

logical v/s physical tags

Physical tags on the other hand provide specific instructions on how to display the text they enclose.

Examples of physical tags include:

: Makes the text bold.

<big>: Makes the text usually one size bigger .

: Makes text italic.

Physical tags were invented to add style to HTML pages because style sheets were not around, though the original intention of HTML was to not have physical tags. Rather than use physical tags to style your HTML pages, you should use style sheets.

HTML Elements

Remember the HTML example from the previous slides:

<html> 
<head> 
<title>My First Webpage</title> 
</head> 
<body> 
This is my first homepage. <b>This text is bold</b> 
</body> 
</html>

This is an HTML element:

<b>This text is bold</b>

html elements

This is an HTML element:

<b>This text is bold</b>

The HTML element begins 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.

html elements

This is also an HTML element:

<body> 
This is my first homepage. <b>This text is bold</b> 
</body>

This HTML element starts with the start tag <body>, and ends with the end tag </body>. The purpose

of the <body> tag is to define the HTML element that contains the body of the HTML document.

Nested Tags

You may have noticed in the example above, the <body> tag also contains other tags, like the tab.

When you enclose an element in with multiple tags, the last tag opened should be the first tag closed.

For example:

 <p><b><em>This is NOT the proper way to close nested tags.</p></em></b>

 <p><b><em>This is the proper way to close nested tags. </em></b></p>

Note: It doesn't matter which tag is first, but they must be closed in the proper order.

Why Use Lowercase Tags?

You may notice we've used lowercase tags even though I said that HTML tags are not case sensitive.

means the same as . The World Wide Web Consortium (W3C), the group responsible for

developing web standards, recommends lowercase tags in their HTML 4 recommendation, and XHTML

(the next generation HTML) requires lowercase tags.

Tag Attributes

Tags can have attributes. Attributes can provide additional information about the HTML elements on

your page. The <tag> tells the browser to do something, while the attribute tells the browser how to do it. For instance, if we add the bgcolor attribute, we can tell the browser that the background color of your page should be blue, like this: <body bgcolor="blue">.

tag attributes

This tag defines an HTML table: <table>. With an added border attribute, you can tell the browser that the table should have no borders: <table border="0">. Attributes always come in name/value pairs like this: name="value". Attributes are always added to the start tag of an HTML element and the value is surrounded by quotes.