This is a primer for producing documents in HTML, the hypertext markup language used on the World Wide Web.
HTML documents are plain-text (also known as ASCII) files that can be created using any text editor (e.g., Emacs or vi on UNIX machines; SimpleText on a Macintosh; Notepad on a Windows machine). You can also use word-processing software if you remember to save your document as "text only with line breaks".
An element is a fundamental component of the structure of a text document. Some examples of elements are heads, tables, paragraphs, and lists. Think of it this way: you use HTML tags to mark the elements of a file for your browser. Elements can contain plain text, other elements, or both.
To denote the various elements in an HTML document, you use tags. HTML tags consist of a left angle bracket (<), a tag name, and a right angle bracket (>). Tags are usually paired (e.g., <H1> and </H1>) to start and end the tag instruction. The end tag looks just like the start tag except a slash (/) precedes the text within the brackets. HTML tags are noted below.
Some elements may include an attribute, which is additional information that is included inside the start tag. For example, you can specify the alignment of images (top, middle, or bottom) by including the appropriate attribute with the image source HTML code. Tags that have optional attributes are noted below.
NOTE: HTML is not case sensitive. <title> is equivalent to <TITLE> or <TiTlE>.
Every HTML document should contain certain standard HTML tags. Each document consists of head and body text. The head contains the title, and the body contains the actual text that is made up of paragraphs, lists, and other elements. Browsers expect specific information because they are programmed according to HTML and SGML specifications.
Required elements are shown in this sample bare-bones document:
<html> <head> <TITLE>A Simple HTML Example</TITLE> </head> <body> <H1>HTML is Easy To Learn</H1> <P>Welcome to the world of HTML. HTML Online!</P> <P>Good luck.</P> </body> </html>
This element tells your browser that the file contains HTML-coded information. The file extension .html also indicates this an HTML document and must be used. (If you are restricted to 8.3 filenames (e.g., LeeHome.htm, use only .htm for your extension.)
The head element identifies the first part of your HTML-coded document that contains the title. The title is shown as part of your browser's window (see below).
The title element contains your document title and identifies its content in a global context. The title is typically displayed in the title bar at the top of the browser window, but not inside the window itself. The title is also what is displayed on someone's hotlist or bookmark list, so choose something descriptive, unique, and relatively short. A title is also used to identify your page for search engines (such as Excite or Infoseek).
For example, you might include a shortened title of a book along with the chapter contents: Taku Ashu: Awards Won. This tells the software name, the platform, and the chapter contents, which is more useful than simply calling the document Awards won.
The second--and largest--part of your HTML document is the body, which contains the content of your document (displayed within the text area of your browser window). The tags explained below are used within the body of your HTML document.
HTML has six levels of headings, numbered 1 through 6, with 1 being the largest. Headings are typically displayed in larger and/or bolder fonts than normal body text. The first heading in each document should be tagged <H1>.
The syntax of the heading element is: <Hy>Text of heading </Hy> where y is a number between 1 and 6 specifying the level of the heading.
Do not skip levels of headings in your document. For example, don't start with a level-one heading (<H1>) and then next use a level-three (<H3>) heading.
Unlike documents in most word processors, carriage returns in HTML files aren't significant. In fact, any amount of whitespace -- including spaces, linefeeds, and carriage returns -- are automatically compressed into a single space when your HTML document is displayed in a browser. So you don't have to worry about how long your lines of text are. Word wrapping can occur at any point in your source file without affecting how the page will be displayed.
In the bare-bones example shown in the Minimal HTML Document section, the first paragraph is coded as
<P>welcome to Taku Ashu's Coral Hut. This page talks about me,my family,our friends and my beloved country Cameroon. Have fun and do sign my guestbook on your wayout!</P>
In the source file there is a line break between the sentences. A Web browser ignores this line break and starts a new paragraph only when it encounters another <P> tag.
Important: You must indicate paragraphs with <P> elements. A browser ignores any indentations or blank lines in the source text. Without <P> elements, the document becomes one large paragraph. (One exception is text tagged as "preformatted," which is explained below.) For example, the following would produce identical output as the first bare-bones HTML example:
<H1>Level-one heading</H1> <P>Welcome to the world of HTML. This is the first paragraph. While short it is still a paragraph! </P> <P>And this is the second paragraph.</P>
NOTE: The </P> closing tag may be omitted. This is because browsers understand that when they encounter a <P> tag, it means that the previous paragraph has ended. However, since HTML now allows certain attributes to be assigned to the <P> tag, it's generally a good idea to include it.
Using the <P> and </P> as a paragraph container means that you can center a paragraph by including the ALIGN=alignment attribute in your source file.
<TT><P ALIGN=CENTER></TT> This is a centered paragraph. [See the formatted version below.] </P>
This is a centered paragraph.
It is also possible to align a paragraph to the right instead, by including the ALIGN=RIGHT attribute. ALIGN=LEFT is the default alignment; if no ALIGN attribute is included, the paragraph will be left-aligned.
HTML supports unnumbered, numbered, and definition lists. You can nest lists too, but use this feature sparingly because too many nested items can get difficult to follow.
Unnumbered Lists
To make an unnumbered, bulleted list,
Below is a sample three-item list:
<UL> <LI> Mamfe <LI> kumba <LI> Limbe </UL>
The output is:
The <LI> items can contain multiple paragraphs. Indicate the paragraphs with the <P> paragraph tags.
Numbered Lists
A numbered list (also called an ordered list, from which the tag name derives) is identical to an unnumbered list, except it uses <OL> instead of <UL>. The items are tagged using the same <LI> tag. The following HTML code:
<OL> <LI> Mamfe <LI> Kumba <LI> Limbe </OL>
produces this formatted output:
Definition Lists
A definition list (coded as <DL>) usually consists of alternating a definition term (coded as <DT>) and a definition definition (coded as <DD>). Web browsers generally format the definition on a new line and indent it.
The following is an example of a definition list:
<DL> <DT> Cameroon <DD>Cameroon is situated in the West of Africa. <DT> she has a population of about 15million <DD> Her capital city is Yaounde </DL>
The output looks like:
The <DT> and <DD> entries can contain multiple paragraphs (indicated by <P> paragraph tags), lists, or other definition information.
Nested Lists
Lists can be nested. You can also have a number of paragraphs, each containing a nested list, in a single list item.
Here is a sample nested list:
<UL> <LI> West African Countries: <UL> <LI> Cameroon <LI> Nigerian <LI> Congo </UL> <LI> South African Countries: <UL> <LI> South Africa <LI> Nambia </UL> </UL>
The nested list is displayed as
Use the<PRE> tag (which stands for "preformatted") to generate text in a fixed-width font. This tag also makes spaces, new lines, and tabs significant -- multiple spaces are displayed as multiple spaces, and lines break in the same locations as in the source HTML file. This is useful for program listings, among other things. For example, the following lines:
<PRE> Cameroon is a third world country with a population of about 15million her capitial city is Yaounde her economic capital is Douala she has ten provinces </PRE>
display as:
Cameroon is a third world country with a population of about 15million her capital city is Yaounde her economic capital is Douala she ha ten provinces
The <BR> tag forces a line break with no extra (white) space between lines. Using <P> elements for short lines of text such as postal addresses results in unwanted additional white space. For example, with :
2013 Treetop Lane,Apt.# 43<BR> Silverspring,MD 20904<BR> U.S.A<BR>
2013 Treetop Lane,Apt.# 43 Silverspring,MD 20904 U.S.A