HyperText Markup Language

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Introduction

The vast majority of people are familiar with surfing the Web. They use a browser, which might be Internet Explorer (IE), Firefox, Opera, or Safari (to name a few). They enter a URL into the address field (or click on a link, or type a search query into a toolbar), and the designated server downloads a Web page using HyperText Transfer Protocol.

A Web page is a basic text file that has been formatted using the HyperText Markup Language (HTML). Today, most Web pages actually comprise a collection of files. The main page is the HTML-formatted page, but it contains references to pictures, video clips, audio clips, and other embedded objects that the client will download along with the main Web page, using the HyperText Transport Protocol (HTTP) to execute the downloads.

But there is an aspect to the World Wide Web (WWW) that few people think about: someone has to design and build those websites. That development task may be executed by a single person or a team of people, depending on the size and complexity of the site. Some do the work in-house, and some outsource the development. In most cases, the development and maintenance work is not done on the live web server. That would be disrupted to users accessing the website. Instead, the developer maintains a complete copy of the website on a test server and does all of their development and modification work there. Once the changes have been completed and tested, the test server is synchronized with the working server and the new website is now online.

How the files are moved from the development platform to the working server varies depending on where the servers are in proximity to one another. If they are within the same corporate website, then the internal corporate file services, such as the Network File System (NFS) or Microsoft file services, can be used. If the working server is being hosted elsewhere in the Internet, it is more common to use protocols like the File Transfer Protocol (FTP) or Secure FTP (SFTP).

Examples of HTML code:

<html>: Turns on HTML formatting. Note that the last line in the material (bottom of the last page) is </html>. The ‘/’ turns off the HTML command, as it does with all commands.

<head>: Turns on the header portion of the document. Note that it is turned off again a few lines down (</head>).

<meta>: META commands allow HTML programmers to embed information in the document header that can be used later for indexing and cataloguing purposes.

<title>: Defines the title element of the page. As before, ‘/’ turns it off.

<table>: Begins a table-formatted entry (the title section, in this case).

<tr>: Defines a table row (The title subhead).

<td>: Table data; the information contained in a table cell.

<img src= …>: The name of whatever image is to be placed at this location in the page. In this case, the image is called HAIOPEN.GIF and is to be aligned to the left side of the page, with a height of 72 and width of 489.

<hr>: Draws a horizontal line where indicated.

<p>: Indicates a paragraph element.


As an exercise, right-click on this page, and choose "View Source" for a more comprehensive look at what HTML really can do.