HTML Headings
Headings are defined with the <h1> to <h6> tags.<h1> defines the most important heading. <h6> defines the least important heading.
Example
Try it yourself » |
Headings Are Important
Use HTML headings for headings only. Don't use headings to make text BIG or bold.Search engines use your headings to index the structure and content of your web pages.
Since users may skim your pages by its headings, it is important to use headings to show the document structure.
H1 headings should be used as main headings, followed by H2 headings, then the less important H3 headings, and so on.
HTML Lines
The <hr /> tag creates a horizontal line in an HTML page.The hr element can be used to separate content:
Example
Try it yourself » |
HTML Comments
Comments can be inserted into the HTML code to make it more readable and understandable. Comments are ignored by the browser and are not displayed.Comments are written like this:
Example
Try it yourself » |
HTML Tip - How to View HTML Source
Have you ever seen a Web page and wondered "Hey! How did they do that?"To find out, right-click in the page and select "View Source" (IE) or "View Page Source" (Firefox), or similar for other browsers. This will open a window containing the HTML code of the page.
 | Examples From This Page |
How to display headings in an HTML document.
Hidden comments
How to insert comments in the HTML source code.
Horizontal lines
How to insert a horizontal line.
HTML Tag Reference
W3Schools' tag reference contains additional information about these tags and their attributes.You will learn more about HTML tags and attributes in the next chapters of this tutorial.
| Tag | Description |
|---|---|
| <html> | Defines an HTML document |
| <body> | Defines the document's body |
| <h1> to <h6> | Defines HTML headings |
| <hr /> | Defines a horizontal line |
| <!--> | Defines a comment |
Editing HTML
HTML can be written and edited using many different editors like Dreamweaver and Visual Studio.However, in this tutorial we use a plain text editor (like Notepad) to edit HTML. We believe using a plain text editor is the best way to learn HTML.
Create Your Own Test Web
If you just want to learn HTML, skip the rest of this chapter.If you want to create a test page on your own computer, just copy the 3 files below to your desktop.
(Right click on each link, and select "save target as" or "save link as")
mainpage.htm
page1.htm
page2.htm
<html><head>
<meta http-equiv="content-type" content="text/html; charset=ISO-8859-1">
</head><body>
<h1>This is my Main Page</h1>
<p>This is some text.</p>
<p><a href="http://www.w3schools.com/html/page1.htm">This is a link to Page 1</a></p>
<p><a href="http://www.w3schools.com/html/page2.htm">This is a link to Page 2</a></p>
</body></html>
After you have copied the files, you can double-click on the file called "mainpage.htm" and see your first web site in action.
Use Your Test Web For Learning
We suggest you experiment with everything you learn at W3Schools by editing your web files with a text editor (like Notepad).Note: If your test web contains HTML markup tags you have not learned, don't panic. You will learn all about it in the next chapters.
.HTM or .HTML File Extension?
When you save an HTML file, you can use either the .htm or the .html file extension. There is no difference, it is entirely up to you.HTML Frames
Vertical framesetHow to make a vertical frameset with three different documents.
<html>
<frameset cols="25%,50%,25%">
<frame src="frame_a.htm" />
<frame src="frame_b.htm" />
<frame src="frame_c.htm" />
</frameset>
</html>
Horizontal frameset
How to make a horizontal frameset with three different documents.
<html>
<frameset rows="25%,50%,25%">
<frame src="frame_a.htm" />
<frame src="frame_b.htm" />
<frame src="frame_c.htm" />
</frameset>
</html>
With frames, you can display more than one HTML document in the same browser window. Each HTML document is called a frame, and each frame is independent of the others.
The disadvantages of using frames are:
- Frames are not expected to be supported in future versions of HTML
- Frames are difficult to use. (Printing the entire page is difficult).
- The web developer must keep track of more HTML documents
The HTML frameset Element
The frameset element holds one or more frame elements. Each frame element can hold a separate document.The frameset element states HOW MANY columns or rows there will be in the frameset, and HOW MUCH percentage/pixels of space will occupy each of them.
The HTML frame Element
The <frame> tag defines one particular window (frame) within a frameset.In the example below we have a frameset with two columns.
The first column is set to 25% of the width of the browser window. The second column is set to 75% of the width of the browser window. The document "frame_a.htm" is put into the first column, and the document "frame_b.htm" is put into the second column:
| <frameset cols="25%,75%"> <frame src="frame_a.htm" /> <frame src="frame_b.htm" /> </frameset> |
Basic Notes - Useful Tips
Tip: If a frame has visible borders, the user can resize it by dragging the border. To prevent a user from doing this, you can add noresize="noresize" to the <frame> tag.Note: Add the <noframes> tag for browsers that do not support frames.
Important: You cannot use the <body></body> tags together with the <frameset></frameset> tags! However, if you add a <noframes> tag containing some text for browsers that do not support frames, you will have to enclose the text in <body></body> tags! See how it is done in the first
Nested HTML Elements
Most HTML elements can be nested (can contain other HTML elements).HTML documents consist of nested HTML elements.
HTML Document Example
| <html> <body> <p>This is my first paragraph.</p> </body> </html> |
HTML Example Explained
The <p> element:| <p>This is my first paragraph.</p> |
The element has a start tag <p> and an end tag </p>.
The element content is: This is my first paragraph.
The <body> element:
| <body> <p>This is my first paragraph.</p> </body> |
The element has a start tag <body> and an end tag </body>.
The element content is another HTML element (a p element).
The <html> element:
| <html> <body> <p>This is my first paragraph.</p> </body> </html> |
The element has a start tag <html> and an end tag </html>.
The element content is another HTML element (the body element).
Don't Forget the End Tag
Some HTML elements might display correctly even if you forget the end tag:| <p>This is a paragraph <p>This is a paragraph |
Never rely on this. Many HTML elements will produce unexpected results and/or errors if you forget the end tag .
Empty HTML Elements
HTML elements with no content are called empty elements.<br> is an empty element without a closing tag (the <br> tag defines a line break).
Tip: In XHTML, all elements must be closed. Adding a slash inside the start tag, like <br />, is the proper way of closing empty elements in XHTML (and XML).
HTML Tip: Use Lowercase Tags
HTML tags are not case sensitive: <P> means the same as <p>. Many web sites use uppercase HTML tags.W3Schools use lowercase tags because the World Wide Web Consortium (W3C) recommends lowercase in HTML 4, and demands lowercase tags in XHTML.
Storing Data on the Client
HTML5 offers two new objects for storing data on the client:- localStorage - stores data with no time limit
- sessionStorage - stores data for one session
In HTML5, the data is NOT passed on by every server request, but used ONLY when asked for. It is possible to store large amounts of data without affecting the website's performance.
The data is stored in different areas for different websites, and a website can only access data stored by itself.
HTML5 uses JavaScript to store and access the data.
The localStorage Object
The localStorage object stores the data with no time limit. The data will be available the next day, week, or year.How to create and access a localStorage:
Example
Try it yourself » |
Example
Try it yourself » |
The sessionStorage Object
The sessionStorage object stores the data for one session. The data is deleted when the user closes the browser window.How to create and access a sessionStorage:
Example
Try it yourself »] |
Example
| <script type="text/javascript"> if (sessionStorage.pagecount) { sessionStorage.pagecount=Number(sessionStorage.pagecount) +1; } else { sessionStorage.pagecount=1; } document.write("Visits "+sessionStorage.pagecount+" time(s) this session."); </script> |
Try it yourself »
Visits 1 time(s) this session.
Refresh the page to see the counter increase.
Close the browser window, and try again, and the counter has been reset.
Tidak ada komentar:
Posting Komentar