Category Archives: Html basic
Html cơ bản
HTML Quick List
HTML Basic Document
<html>
<head>
<title>Title of document goes here</title>
</head>
<body>
Visible text goes here…
</body>
</html>
Heading Elements
<h1>Largest Heading</h1>
<h2> . . . </h2>
<h3> . . . </h3>
<h4> . . . </h4>
<h5> . . . </h5>
<h6>Smallest Heading</h6>
Text Elements
<p>This is a paragraph</p>
<br /> (line break)
<hr /> (horizontal rule)
<pre>This text is preformatted</pre>
Logical Styles
<em>This text is emphasized</em>
<strong>This text is strong</strong>
<code>This is some computer code</code>
Physical Styles
<b>This text is bold</b>
<i>This text is italic</i>
Links
Ordinary link: <a href=”http://www.example.com/”>Link-text goes here</a>
Image-link: <a href=”http://www.example.com/”><img src=”URL” alt=”Alternate Text” /></a>
Mailto link: <a href=”mailto:webmaster@example.com”>Send e-mail</a>
A named anchor:
<a name=”tips”>Tips Section</a>
<a href=”#tips”>Jump to the Tips Section</a>
Unordered list
<ul>
<li>Item</li>
<li>Item</li>
</ul>
Ordered list
<ol>
<li>First item</li>
<li>Second item</li>
</ol>
Definition list
<dl>
<dt>First term</dt>
<dd>Definition</dd>
<dt>Next term</dt>
<dd>Definition</dd>
</dl>
Tables
<table border=”1″>
<tr>
<th>Tableheader</th>
<th>Tableheader</th>
</tr>
<tr>
<td>sometext</td>
<td>sometext</td>
</tr>
</table>
Frames
<frameset cols=”25%,75%”>
<frame src=”page1.htm” />
<frame src=”page2.htm” />
</frameset>
Forms
<form action=”http://www.example.com/test.asp” method=”post/get”>
<input type=”text” name=”email” size=”40″ maxlength=”50″ />
<input type=”password” />
<input type=”checkbox” checked=”checked” />
<input type=”radio” checked=”checked” />
<input type=”submit” value=”Send” />
<input type=”reset” />
<input type=”hidden” />
<select>
<option>Apples</option>
<option selected=”selected”>Bananas</option>
<option>Cherries</option>
</select>
<textarea name=”comment” rows=”60″ cols=”20″></textarea>
</form>
Entities
< is the same as <
> is the same as >
© is the same as ©
Other Elements
<!– This is a comment –>
<blockquote>
Text quoted from a source.
</blockquote>
<address>
Written by W3Schools.com<br />
<a href=”mailto:us@example.org”>Email us</a><br />
Address: Box 564, Disneyland<br />
Phone: +12 34 56 78
</address>
HTML Color Names
Color Names Supported by All Browsers
147 color names are defined in the HTML and CSS color specification (17 standard colors plus 130 more). The table below lists them all, along with their hexadecimal values.
Tip: The 17 standard colors are: aqua, black, blue, fuchsia, gray, grey, green, lime, maroon, navy, olive, purple, red, silver, teal, white, and yellow.
Click on a color name (or a hex value) to view the color as the background-color along with different text colors:
Sorted by Color Name
Same list sorted by hex values
HTML Colors
Colors are displayed combining RED, GREEN, and BLUE light.
Color Values
HTML colors are defined using a hexadecimal notation (HEX) for the combination of Red, Green, and Blue color values (RGB).
The lowest value that can be given to one of the light sources is 0 (in HEX: 00). The highest value is 255 (in HEX: FF).
HEX values are specified as 3 pairs of two-digit numbers, starting with a # sign.
Color Values
|
16 Million Different Colors
The combination of Red, Green, and Blue values from 0 to 255, gives more than 16 million different colors (256 x 256 x 256).
Web Safe Colors?
Some years ago, when computers supported max 256 different colors, a list of 216 “Web Safe Colors” was suggested as a Web standard, reserving 40 fixed system colors.
The 216 cross-browser color palette was created to ensure that all computers would display the colors correctly when running a 256 color palette.
This is not important today, since most computers can display millions of different colors. Anyway, here is the list:
| 000000 | 000033 | 000066 | 000099 | 0000CC | 0000FF |
| 003300 | 003333 | 003366 | 003399 | 0033CC | 0033FF |
| 006600 | 006633 | 006666 | 006699 | 0066CC | 0066FF |
| 009900 | 009933 | 009966 | 009999 | 0099CC | 0099FF |
| 00CC00 | 00CC33 | 00CC66 | 00CC99 | 00CCCC | 00CCFF |
| 00FF00 | 00FF33 | 00FF66 | 00FF99 | 00FFCC | 00FFFF |
| 330000 | 330033 | 330066 | 330099 | 3300CC | 3300FF |
| 333300 | 333333 | 333366 | 333399 | 3333CC | 3333FF |
| 336600 | 336633 | 336666 | 336699 | 3366CC | 3366FF |
| 339900 | 339933 | 339966 | 339999 | 3399CC | 3399FF |
| 33CC00 | 33CC33 | 33CC66 | 33CC99 | 33CCCC | 33CCFF |
| 33FF00 | 33FF33 | 33FF66 | 33FF99 | 33FFCC | 33FFFF |
| 660000 | 660033 | 660066 | 660099 | 6600CC | 6600FF |
| 663300 | 663333 | 663366 | 663399 | 6633CC | 6633FF |
| 666600 | 666633 | 666666 | 666699 | 6666CC | 6666FF |
| 669900 | 669933 | 669966 | 669999 | 6699CC | 6699FF |
| 66CC00 | 66CC33 | 66CC66 | 66CC99 | 66CCCC | 66CCFF |
| 66FF00 | 66FF33 | 66FF66 | 66FF99 | 66FFCC | 66FFFF |
| 990000 | 990033 | 990066 | 990099 | 9900CC | 9900FF |
| 993300 | 993333 | 993366 | 993399 | 9933CC | 9933FF |
| 996600 | 996633 | 996666 | 996699 | 9966CC | 9966FF |
| 999900 | 999933 | 999966 | 999999 | 9999CC | 9999FF |
| 99CC00 | 99CC33 | 99CC66 | 99CC99 | 99CCCC | 99CCFF |
| 99FF00 | 99FF33 | 99FF66 | 99FF99 | 99FFCC | 99FFFF |
| CC0000 | CC0033 | CC0066 | CC0099 | CC00CC | CC00FF |
| CC3300 | CC3333 | CC3366 | CC3399 | CC33CC | CC33FF |
| CC6600 | CC6633 | CC6666 | CC6699 | CC66CC | CC66FF |
| CC9900 | CC9933 | CC9966 | CC9999 | CC99CC | CC99FF |
| CCCC00 | CCCC33 | CCCC66 | CCCC99 | CCCCCC | CCCCFF |
| CCFF00 | CCFF33 | CCFF66 | CCFF99 | CCFFCC | CCFFFF |
| FF0000 | FF0033 | FF0066 | FF0099 | FF00CC | FF00FF |
| FF3300 | FF3333 | FF3366 | FF3399 | FF33CC | FF33FF |
| FF6600 | FF6633 | FF6666 | FF6699 | FF66CC | FF66FF |
| FF9900 | FF9933 | FF9966 | FF9999 | FF99CC | FF99FF |
| FFCC00 | FFCC33 | FFCC66 | FFCC99 | FFCCCC | FFCCFF |
| FFFF00 | FFFF33 | FFFF66 | FFFF99 | FFFFCC | FFFFFF |
HTML Iframes
Syntax for adding an iframe:
| http://emURL/em |
The URL points to the location of the separate page.
Iframe – Set Height and Width
The height and width attributes are used to specify the height and width of the iframe.
The attribute values are specified in pixels by default, but they can also be in percent (like “80%”).
Example
|
Iframe – Remove the Border
The frameborder attribute specifies whether or not to display a border around the iframe.
Set the attribute value to “0” to remove the border:
Example
|
Use iframe as a Target for a Link
An iframe can be used as the target frame for a link.
The target attribute of a link must refer to the name attribute of the iframe:
Example
|
HTML iframe Tag
| Tag | Description |
|---|---|
| <iframe> | Defines an inline sub window (frame) |
HTML Forms and Input
HTML Forms are used to select different kinds of user input.
HTML Forms
HTML forms are used to pass data to a server.
A form can contain input elements like text fields, checkboxes, radio-buttons, submit buttons and more. A form can also contain select lists, textarea, fieldset, legend, and label elements.
The <form> tag is used to create an HTML form:
| <form> . input elements . </form> |
HTML Forms – The Input Element
The most important form element is the input element.
The input element is used to select user information.
An input element can vary in many ways, depending on the type attribute. An input element can be of type text field, checkbox, password, radio button, submit button, and more.
The most used input types are described below.
Text Fields
<input type=”text” /> defines a one-line input field that a user can enter text into:
| <form> First name: <input type=”text” name=”firstname” /><br /> Last name: <input type=”text” name=”lastname” /> </form> |
How the HTML code above looks in a browser:
First name:
Last name: Note: The form itself is not visible. Also note that the default width of a text field is 20 characters.
Password Field
<input type=”password” /> defines a password field:
| <form> Password: <input type=”password” name=”pwd” /> </form> |
How the HTML code above looks in a browser:
Password:
Note: The characters in a password field are masked (shown as asterisks or circles).
Radio Buttons
<input type=”radio” /> defines a radio button. Radio buttons let a user select ONLY ONE one of a limited number of choices:
| <form> <input type=”radio” name=”sex” value=”male” /> Male<br /> <input type=”radio” name=”sex” value=”female” /> Female </form> |
How the HTML code above looks in a browser:
Male
Female
Checkboxes
<input type=”checkbox” /> defines a checkbox. Checkboxes let a user select ONE or MORE options of a limited number of choices.
| <form> <input type=”checkbox” name=”vehicle” value=”Bike” /> I have a bike<br /> <input type=”checkbox” name=”vehicle” value=”Car” /> I have a car </form> |
How the HTML code above looks in a browser:
I have a bike
I have a car
Submit Button
<input type=”submit” /> defines a submit button.
A submit button is used to send form data to a server. The data is sent to the page specified in the form’s action attribute. The file defined in the action attribute usually does something with the received input:
| <form name=”input” action=”html_form_action.asp” method=”get”> Username: <input type=”text” name=”user” /> <input type=”submit” value=”Submit” /> </form> |
How the HTML code above looks in a browser:
Username:
If you type some characters in the text field above, and click the “Submit” button, the browser will send your input to a page called “html_form_action.asp”. The page will show you the received input.
More Input Examples
Radio buttons
How to create radio buttons.
Checkboxes
How to create checkboxes. A user can select or unselect a checkbox.
Simple drop-down list
How to create a simple drop-down list.
Drop-down list with a pre-selected value
How to create a drop-down list with a pre-selected value.
Textarea
How to create a multi-line text input control. In a text-area the user can write an unlimited number of characters.
Create a button
How to create a button.
Form Examples
Fieldset around form-data
How to create a border around elements in a form.
Form with text fields and a submit button
How to create a form with two text fields and a submit button.
Form with checkboxes
How to create a form with two checkboxes and a submit button.
Form with radio buttons
How to create a form with two radio buttons, and a submit button.
Send e-mail from a form
How to send e-mail from a form.
HTML Form Tags
| Tag | Description |
|---|---|
| <form> | Defines an HTML form for user input |
| <input /> | Defines an input control |
| <textarea> | Defines a multi-line text input control |
| <label> | Defines a label for an input element |
| <fieldset> | Defines a border around elements in a form |
| <legend> | Defines a caption for a fieldset element |
| <select> | Defines a select list (drop-down list) |
| <optgroup> | Defines a group of related options in a select list |
| <option> | Defines an option in a select list |
| <button> | Defines a push button |
HTML Lists
The most common HTML lists are ordered and unordered lists:
HTML Lists
|
HTML Unordered Lists
An unordered list starts with the <ul> tag. Each list item starts with the <li> tag.
The list items are marked with bullets (typically small black circles).
| <ul> <li>Coffee</li> <li>Milk</li> </ul> |
How the HTML code above looks in a browser:
- Coffee
- Milk
HTML Ordered Lists
An ordered list starts with the <ol> tag. Each list item starts with the <li> tag.
The list items are marked with numbers.
| <ol> <li>Coffee</li> <li>Milk</li> </ol> |
How the HTML code above looks in a browser:
- Coffee
- Milk
HTML Definition Lists
A definition list is a list of items, with a description of each item.
The <dl> tag defines a definition list.
The <dl> tag is used in conjunction with <dt> (defines the item in the list) and <dd> (describes the item in the list):
| <dl> <dt>Coffee</dt> <dd>- black hot drink</dd> <dt>Milk</dt> <dd>- white cold drink</dd> </dl> |
How the HTML code above looks in a browser:
- Coffee
- – black hot drink
- Milk
- – white cold drink
Basic Notes – Useful Tips
Tip: Inside a list item you can put text, line breaks, images, links, other lists, etc.
HTML List Tags
| Tag | Description |
|---|---|
| <ol> | Defines an ordered list |
| <ul> | Defines an unordered list |
| <li> | Defines a list item |
| <dl> | Defines a definition list |
| <dt> | Defines an item in a definition list |
| <dd> | Defines a description of an item in a definition list |
HTML Tables
Tables are defined with the <table> tag.
A table is divided into rows (with the <tr> tag), and each row is divided into data cells (with the <td> tag). td stands for “table data,” and holds the content of a data cell. A <td> tag can contain text, links, images, lists, forms, other tables, etc.
Table Example
| <table border=”1″> <tr> <td>row 1, cell 1</td> <td>row 1, cell 2</td> </tr> <tr> <td>row 2, cell 1</td> <td>row 2, cell 2</td> </tr> </table> |
How the HTML code above looks in a browser:
| row 1, cell 1 | row 1, cell 2 |
| row 2, cell 1 | row 2, cell 2 |
HTML Tables and the Border Attribute
If you do not specify a border attribute, the table will be displayed without borders. Sometimes this can be useful, but most of the time, we want the borders to show.
To display a table with borders, specify the border attribute:
| <table border=”1″> <tr> <td>Row 1, cell 1</td> <td>Row 1, cell 2</td> </tr> </table> |
HTML Table Headers
Header information in a table are defined with the <th> tag.
All major browsers will display the text in the <th> element as bold and centered.
| <table border=”1″> <tr> <th>Header 1</th> <th>Header 2</th> </tr> <tr> <td>row 1, cell 1</td> <td>row 1, cell 2</td> </tr> <tr> <td>row 2, cell 1</td> <td>row 2, cell 2</td> </tr> </table> |
How the HTML code above looks in your browser:
| Header 1 | Header 2 |
|---|---|
| row 1, cell 1 | row 1, cell 2 |
| row 2, cell 1 | row 2, cell 2 |
HTML Table Tags
| Tag | Description |
|---|---|
| <table> | Defines a table |
| <th> | Defines a table header |
| <tr> | Defines a table row |
| <td> | Defines a table cell |
| <caption> | Defines a table caption |
| <colgroup> | Defines a group of columns in a table, for formatting |
| <col /> | Defines attribute values for one or more columns in a table |
| <thead> | Groups the header content in a table |
| <tbody> | Groups the body content in a table |
| <tfoot> | Groups the footer content in a table |
HTML Images
HTML Images – The <img> Tag and the Src Attribute
In HTML, images are defined with the <img> tag.
The <img> tag is empty, which means that it contains attributes only, and has no closing tag.
To display an image on a page, you need to use the src attribute. Src stands for “source”. The value of the src attribute is the URL of the image you want to display.
Syntax for defining an image:
| <img src=”url” alt=”some_text“/> |
The URL points to the location where the image is stored. An image named “boat.gif”, located in the “images” directory on “www.w3schools.com” has the URL: http://www.w3schools.com/images/boat.gif.
The browser displays the image where the <img> tag occurs in the document. If you put an image tag between two paragraphs, the browser shows the first paragraph, then the image, and then the second paragraph.
HTML Images – The Alt Attribute
The required alt attribute specifies an alternate text for an image, if the image cannot be displayed.
The value of the alt attribute is an author-defined text:
| <img src=”boat.gif” alt=”Big Boat” /> |
The alt attribute provides alternative information for an image if a user for some reason cannot view it (because of slow connection, an error in the src attribute, or if the user uses a screen reader).
HTML Images – Set Height and Width of an Image
The height and width attributes are used to specify the height and width of an image.
The attribute values are specified in pixels by default:
| <img src=”pulpit.jpg” alt=”Pulpit rock” width=”304″ height=”228″ /> |
Tip: It is a good practice to specify both the height and width attributes for an image. If these attributes are set, the space required for the image is reserved when the page is loaded. However, without these attributes, the browser does not know the size of the image. The effect will be that the page layout will change during loading (while the images load).
Basic Notes – Useful Tips
Note: If an HTML file contains ten images – eleven files are required to display the page right. Loading images take time, so my best advice is: Use images carefully.
Note: When a web page is loaded, it is the browser, at that moment, that actually gets the image from a web server and inserts it into the page. Therefore, make sure that the images actually stay in the same spot in relation to the web page, otherwise your visitors will get a broken link icon. The broken link icon is shown if the browser cannot find the image.
HTML Image Tags
| Tag | Description |
|---|---|
| <img /> | Defines an image |
| <map> | Defines an image-map |
| <area /> | Defines a clickable area inside an image-map |
HTML Links
Links are found in nearly all Web pages. Links allow users to click their way from page to page.
 |
Try it Yourself – Examples |
HTML links
How to create links in an HTML document.
(You can find more examples at the bottom of this page)
HTML Hyperlinks (Links)
A hyperlink (or link) is a word, group of words, or image that you can click on to jump to a new document or a new section within the current document.
When you move the cursor over a link in a Web page, the arrow will turn into a little hand.
Links are specified in HTML using the <a> tag.
The <a> tag can be used in two ways:
- To create a link to another document, by using the href attribute
- To create a bookmark inside a document, by using the name attribute
HTML Link Syntax
The HTML code for a link is simple. It looks like this:
| <a href=”url“>Link text</a> |
The href attribute specifies the destination of a link.
Example
| <a href=”http://www.w3schools.com/”>Visit W3Schools</a> |
which will display like this: Visit W3Schools
Clicking on this hyperlink will send the user to W3Schools’ homepage.
Tip: The “Link text” doesn’t have to be text. You can link from an image or any other HTML element.
HTML Links – The target Attribute
The target attribute specifies where to open the linked document.
The example below will open the linked document in a new browser window or a new tab:
Example
|
HTML Links – The name Attribute
The name attribute specifies the name of an anchor.
The name attribute is used to create a bookmark inside an HTML document.
Note:
The upcoming HTML5 standard suggest using the id attribute instead of the name attribute for specifying the name of an anchor.
Using the id attribute actually works also for HTML4 in all modern browsers.
Bookmarks are not displayed in any special way. They are invisible to the reader.
Example
A named anchor inside an HTML document:
| <a name=”tips”>Useful Tips Section</a> |
Create a link to the “Useful Tips Section” inside the same document:
| <a href=”#tips”>Visit the Useful Tips Section</a> |
Or, create a link to the “Useful Tips Section” from another page:
| <a href=”http://www.w3schools.com/html_links.htm#tips”> Visit the Useful Tips Section</a> |
Basic Notes – Useful Tips
Note: Always add a trailing slash to subfolder references. If you link like this: href=”http://www.w3schools.com/html”, you will generate two requests to the server, the server will first add a slash to the address, and then create a new request like this: href=”http://www.w3schools.com/html/”.
Tip: Named anchors are often used to create “table of contents” at the beginning of a large document. Each chapter within the document is given a named anchor, and links to each of these anchors are put at the top of the document.
Tip: If a browser does not find the named anchor specified, it goes to the top of the document. No error occurs.
HTML Styles – CSS
CSS is used to style HTML elements.
Look! Styles and colorsThis text is in Verdana and red This text is in Times and blue This text is 30 pixels high |
Styling HTML with CSS
CSS was introduced together with HTML 4, to provide a better way to style HTML elements.
CSS can be added to HTML in the following ways:
- in separate style sheet files (CSS files)
- in the style element in the HTML head section
- in the style attribute in single HTML elements
Using the HTML Style Attribute
It is time consuming and not very practical to style HTML elements using the style attribute.
The preferred way to add CSS to HTML, is to put CSS syntax in separate CSS files.
However, in this HTML tutorial we will introduce you to CSS using the style attribute. This is done to simplify the examples. It also makes it easier for you to edit the code and try it yourself.
You can learn everything about CSS in our CSS Tutorial.
HTML Style Example – Background Color
The background-color property defines the background color for an element:
Example
|
The background-color property makes the “old” bgcolor attribute obsolete.
HTML Style Example – Font, Color and Size
The font-family, color, and font-size properties defines the font, color, and size of the text in an element:
Example
|
The font-family, color, and font-size properties make the old <font> tag obsolete.
HTML Style Example – Text Alignment
The text-align property specifies the horizontal alignment of text in an element:
Example
|
The text-align property makes the old <center> tag obsolete.
Deprecated Tags and Attributes
In HTML 4, several tags and attributes were deprecated. Deprecated means that they will not be supported in future versions of HTML.
The message is clear: Avoid using deprecated tags and attributes!
These tags and attributes should be avoided:
| Tags | Description |
|---|---|
| <center> | Deprecated. Defines centered content |
| <font> and <basefont> | Deprecated. Defines HTML fonts |
| <s> and <strike> | Deprecated. Defines strikethrough text |
| <u> | Deprecated. Defines underlined text |
| Attributes | Description |
| align | Deprecated. Defines the alignment of text |
| bgcolor | Deprecated. Defines the background color |
| color | Deprecated. Defines the text color |
For all of the above: Use styles instead!
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