READING-NOTE

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When creating a web page, you add tags (known as markup) to the contents of the page. These tags provide extra meaning and allow browsers to show users the appropriate structure for the page.

Headings

HTML has six “levels” of headings: h1> is used for main headings h2> is used for subheadings If there are further sections under the subheadings then the h3> element is used, and so on… Browsers display the contents of headings at different sizes. The contents of an h1> element is the largest, and the contents of an h6> element is the smallest. The exact size at which each browser shows the headings can vary slightly. Users can also adjust the size of text in their browser. You will see how to control the size of text, its color, and the fonts used when we come to look at CSS.

Paragraph

To create a paragraph, surround the words that make up the paragraph with an opening p> tag and closing /p> tag. By default, a browser will show each paragraph on a new line with some space between it and any subsequent paragraphs.

Bold & It alic

# <b

By enclosing words in the tags b and /b we can make characters appear bold. The b element also represents a section of text that would be presented in a visually different way (for example key words in a paragraph) although the use of the b element does not imply any additional meaning.

# <i

By enclosing words in the tags i and /i we can make characters appear italic. The i element also represents a section of text that would be said in a different way from surrounding content — such as technical terms, names of ships, foreign words, thoughts, or other terms that would usually be italicized.

Superscript & Subscript

<sup

The sup element is used to contain characters that should be superscript such as the suffixes of dates or mathematical concepts like raising a number to a power such as 22.

<sub

The sub element is used to contain characters that should be subscript. It is commonly used with foot notes or chemical formulas such as H20.

White Sp ace

In order to make code easier to read, web page authors often add extra spaces or start some elements on new lines. When the browser comes across two or more spaces next to each other, it only displays one space. Similarly if it comes across a line break, it treats that as a single space too. This is known as white space collapsing. You will often see that web page authors take advantage of white space collapsing to indent their code in order to make it easier to follow.

Line Breaks & Horizontal Rules

br />

As you have already seen, the browser will automatically show each new paragraph or heading on a new line. But if you wanted to add a line break inside the middle of a paragraph you can use the line break tag br />.

hr />

To create a break between themes — such as a change of topic in a book or a new scene in a play — you can add a horizontal rule between sections using the hr /> tag. There are a few elements that do not have any words between an opening and closing tag. They are known as empty elements and they are written differently. An empty element usually has only one tag. Before the closing angled bracket of an empty element there will often be a space and a forward slash character. Some web page authors miss this out but it is a good habit to get into.

St rong & Emph asis

strong>

The use of the strong> element indicates that its content has strong importance. For example, the words contained in this element might be said with strong emphasis. By default, browsers will show the contents of a strong> element in bold.

em>

The em> element indicates emphasis that subtly changes the meaning of a sentence. By default browsers will show the contents of an em> element in italic.

Quotations

<blockquote>

The blockquote element is used for longer quotes that take up an entire paragraph. Note how the p> element is still used inside the blockquote element. Browsers tend to indent the contents of the blockquote element, however you should not use this element just to indent a piece of text — rather you should achieve this effect using CSS.

q>

The q> element is used for shorter quotes that sit within a paragraph. Browsers are supposed to put quotes around the q> element, however Internet Explorer does not — therefore many people avoid using the q> element. Both elements may use the cite attribute to indicate where the quote is from. Its value should be a URL that will have more information about the source of the quotation.

Abb reviations & Acronyms

abbr>

If you use an abbreviation or an acronym, then the abbr> element can be used. A title attribute on the opening tag is used to specify the full term. In HTML 4 there was a separate element for acronyms. To spell out the full form of the acronym, the title attribute was used (as with the abbr> element above). HTML5 just uses the abbr> element for both abbreviations and acronyms.

Citations & Definitions

When you are referencing a piece of work such as a book, film or research paper, the cite> element can be used to indicate where the citation is from. In HTML5, cite> should not really be used for a person’s name — but it was allowed in HTML 4, so most people are likely to continue to use it. Browsers will render the content of a cite> element in italics.

dfn>

The first time you explain some new terminology (perhaps an academic concept or some jargon) in a document, it is known as the defining instance of it. The dfn> element is used to indicate the defining instance of a new term. Some browsers show the content of the dfn> element in italics. Safari and Chrome do not change its appearance.

Auth or Details

address

The address element has quite a specific use: to contain contact details for the author of the page. It can contain a physical address, but it does not have to. For example, it may also contain a phone number or email address. Browsers often display the content of the address element in italics. You may also be interested in something called the hCard microformat for adding physical address information to your markup.

Changes to Content

<ins

<del

The ins element can be used to show content that has been inserted into a document, while the del element can show text that has been deleted from it. The content of a ins element is usually underlined, while the content of a del element usually has a line through it.

<s

The s element indicates something that is no longer accurate or relevant (but that should not be deleted). Visually the content of an s element will usually be displayed with a line through the center. Older versions of HTML had a u element for content that was underlined, but this is being phased out.

Introducing CSS

CSS Associates Style rules with HT ML elements

This rule indicates that all p elements should be shown in the Arial typeface. Selectors indicate which element the rule applies to. The same rule can apply to more than one element if you separate the element names with commas. Declarations indicate how the elements referred to in the selector should be styled. Declarations are split into two parts (a property and a value), and are separated by a colon.

CSS Properties Affect How El ements Are Dis played

CSS declarations sit inside curly brackets and each is made up of two parts: a property and a value, separated by a colon. You can specify several properties in one declaration, each separated by a semi-colon.

This rule indicates that all h1, h2 and h3 elements should be shown in the Arial typeface, in a yellow color. Properties indicate the aspects of the element you want to change. For example, color, font, width, height and border. Values specify the settings you want to use for the chosen properties. For example, if you want to specify a color property then the value is the color you want the text in these elements to be.

Usi ng External CSS

external-css.html HTML The link> element can be used in an HTML document to tell the browser where to find the CSS file used to style the page. It is an empty element (meaning it does not need a closing tag), and it lives inside the head> element. It should use three attributes:

href

This specifies the path to the CSS file (which is often placed in a folder called css or styles).

type

This attribute specifies the type of document being linked to. The value should be text/css.

rel

This specifies the relationship between the HTML page and the file it is linked to. The value should be stylesheet when linking to a CSS file. An HTML page can use more than one CSS style sheet. To do this it could have a link> element for every CSS file it uses. For example, some authors use one CSS file to control the presentation (such as fonts and colors) and a second to control the layout.