HTML and CSS Basics
- 2. What is HTML
&CSS
HTML, HyperText Markup Language, gives content structure and
meaning by defining that content as, for example, headings,
paragraphs, or images. CSS, or Cascading Style Sheets, is a
presentation language created to style the appearance of
content—using, for example, fonts or colors.
The two languages—HTML and CSS—are independent of one
another and should remain that way. CSS should not be written
inside of an HTML document and vice versa. As a rule, HTML will
always represent content, and CSS will always represent the
appearance of that content.
- 3. Common
Terms
Elements – A designator that define the structure and content of
objects within a page. Some of the more frequently used elements
include multiple levels of headings (identified as <h1> through
<h6> elements) and paragraphs (identified as the <p> element);
the list goes on to include the <a>, <div>, <span>, <strong>, and
<em> elements, and many more.
- 4. Common
Terms
Tags -The use of less-than and greater-than angle brackets
surrounding an element creates what is known as a tag.Tags most
commonly occur in pairs of opening and closing tags.The content
that falls between the opening and closing tags is the content of
that element. An anchor link, for example, will have an opening
tag of <a> and a closing tag of </a>.What falls between these two
tags will be the content of the anchor link.
OpeningTag - An opening tag marks the beginning of an element. It
consists of a less-than sign followed by an element’s name, and then
ends with a greater-than sign; for example, <div>.
ClosingTag - marks the end of an element. It consists of a less-than
sign followed by a forward slash and the element’s name, and then
ends with a greater-than sign; for example, </div>.
- 5. Common
Terms
Attributes - Properties used to provide additional information
about an element.The most common attributes include the id
attribute, which identifies an element; the class attribute, which
classifies an element; the src attribute, which specifies a source for
embeddable content; and the href attribute, which provides a
hyperlink reference to a linked resource.
Attributes are defined within the opening tag, after an element’s
name. Generally attributes include a name and a value.The format
for these attributes consists of the attribute name followed by an
equals sign and then a quoted attribute value.
- 6. Demo
The preceding code will display the text “Meadows Resources” on
the web page and will take users to
http://meadowsresources.com/ upon clicking the “Meadows
Resources” text.The anchor element is declared with the opening
<a> and closing </a> tags encompassing the text, and the
hyperlink reference attribute and value are declared with
href="http://meadowsresources.com" in the opening tag.
- 8. HTML
Document
Structure
HTML documents are plain text documents saved with an .html file
extension rather than a .txt file extension.To begin writing HTML,
you first need a plain text editor that you are comfortable using.
Sadly this does not include MicrosoftWord or Pages, as those are
rich text editors.Two of the more popular plain text editors for
writing HTML and CSS are Dreamweaver and SublimeText. Free
alternatives also include Notepad++ forWindows andTextWrangler
for Mac.
All HTML documents have a required structure that includes the
following declaration and elements: <!DOCTYPE html>, <html>,
<head>, and <body>.
- 9. HTML
Document
Structure
The document type declaration, or <!DOCTYPE html>, informs web
browsers which version of HTML is being used and is placed at the
very beginning of the HTML document. Because we’ll be using the
latest version of HTML, our document type declaration is simply
<!DOCTYPE html>. Following the document type declaration, the
<html> element signifies the beginning of the document.
- 10. HTML
Document
Structure
Inside the <html> element, the <head> element identifies the top of
the document, including any metadata (accompanying information
about the page).The content inside the <head> element is not
displayed on the web page itself. Instead, it may include the
document title (which is displayed on the title bar in the browser
window), links to any external files, or any other beneficial
metadata. All of the visible content within the web page will fall
within the <body> element.
- 11. HTML
Document
Structure
The preceding code shows the document beginning with the
document type declaration, <!DOCTYPE html>, followed directly by
the <html> element. Inside the <html> element come the <head>
and <body> elements.The <head> element includes the character
encoding of the page via the <meta charset="utf-8"> tag and the
title of the document via the <title> element.The <body> element
includes a heading via the <h1> element and a paragraph via the <p>
element. Because both the heading and paragraph are nested
within the <body> element, they are visible on the web page.
- 12. HTML
Document
Structure
When an element is placed inside of another element, also known as
nested, it is a good idea to indent that element to keep the
document structure well organized and legible. In the previous
code, both the <head> and <body> elements were nested—and
indented—inside the <html> element.The pattern of indenting for
elements continues as new elements are added inside the <head>
and <body> elements.
- 13. SelfClosing
Elements
In the previous example, the <meta> element had only one tag and
didn’t include a closing tag. Fear not, this was intentional. Not all
elements consist of opening and closing tags. Some elements
simply receive their content or behavior from attributes within a
single tag.The <meta> element is one of these elements.The
content of the previous <meta> element is assigned with the use of
the charset attribute and value. Other common self closing
elements include: <br> <embed> <hr> <img> <input> <link> <meta>
<param> <source> <wbr>
- 14. ProTip
The structure outlined here, making use of the <!DOCTYPE html>
document type and <html>, <head>, and <body> elements, is quite
common.We’ll want to keep this document structure handy, as we’ll
be using it often as we create new HTML documents.
- 15. Code
Validation
No matter how careful we are when writing our code, we will
inevitably make mistakes.Thankfully, when writing HTML and CSS
we have validators to check our work.TheW3C has built both HTML
and CSS validators that will scan code for mistakes.Validating our
code not only helps it render properly across all browsers, but also
helps teach us the best practices for writing code.