HTML (HyperText Markup Language) is used to give content to a web page and instructs web browsers on how to structure that content.
An HTML element is a piece of content in an HTML document and uses the following syntax: opening tag + content + closing tag.
<p> Hello World! </p>The syntax for a single HTML tag is an opening angle bracket < followed by the element name and a closing angle bracket > . Here is an example of an opening
<div>The content of an HTML element is the information between the opening and closing tags of an element.
The element represents the content of an HTML document. Contentinside tags are rendered on the web browsers. Note: There can be only one element in a document.
<body>
<h1> Learn to code with Codecademy :) </h1>
</body >HTML is organized into a family tree structure. HTML elements can have parents, grandparents, siblings, children, grandchildren, etc.
<body>
<div>
<h1> It's div's child and body's grandchild </h1>
<h2> It's h1's sibling </h2>
</div>
</body>HTML can use six different levels of heading elements. The heading elements are ordered from the highest level h1 to the lowest level h6.
<h1> Breaking News </ h1 >
<h2> This is the 1st subheading </h2>
<h3> This is the 2nd subheading </h3>
...
<h6> This is the 5th subheading </h6>The div element is used as a container that divides an HTML document into sections and is short for “division”. div elements can contain flow content such as headings, paragraphs, links, images, etc.
<div>
<h1> A section of grouped elements </h1>
<p> Here’s some text for the section </p>
</div>
<div>
<h1> Second section of grouped elements </h1>
<p> Here’s some text </p>
</ div >HTML attributes are values added to the opening tag of an element to configure the element or change the element’s default behavior. In the provided example, we are giving the
(paragraph) element a unique identifier using the id attribute and changing the color of the default text using the style attribute.
<p id = "my-paragraph" style = "color: green;" > Here’s some text for a paragraph
that is being altered by HTML attributes </p>HTML attributes consist of a name and a value using the following syntax:name="value"and can be added to the opening tag of an HTML element to configure or change the behavior of the element.
<elementName name = "value"> </elementName>In HTML, specific and unique id attributes can be assigned to different elements in order to differentiate between them.When needed, the id value can be called upon by CSS and JavaScript to manipulate, format, and perform specific instructions on that element and that element only. Valid id attributes should begin with a letter and should onlycontain letters ( a-Z ), digits ( 0-9 ), hyphens ( - ), underscores ( _ ), and periods( . ).
<h1 id= "A1"> Hello World </h1>The
paragraph element contains and displays a block of text.
The element is an inline container for text and can be used to group text for styling purposes. However, as is a generic container to separate pieces of text from a larger body of text, its use should be avoided if a more semantic element is available.
<p> <span> This text </span> may be styled differently than the surrounding text.</p>The emphasis element emphasizes text and browsers will usually italicize the emphasized text by default.
The element highlights important, serious, or urgent text and browsers will normally render this highlighted text in bold by default.
The br line break element will create a line break in text and is especially useful where a division of text is required, like in a postal address. The line break element requires only an opening tag and must not have a closing tag.
The li list item element create list items inside:
- Unordered lists ul
- Ordered lists ol
The ul unordered list element is used to create a list of items in no particular order. Each individual list item will have a bullet point by default.
<ul>
<li> Play more music 🎸 </li>
<li> Read more books 📚 </li>
</ul>The ol ordered list element creates a list of items in sequential order. Each list item appears numbered by default.
< ol >
< li > Preheat oven to 325 F 👩 🍳 </ li >
< li > Drop cookie dough 🍪 </ li >
< li > Bake for 15 min ⏰ </ li >
</ ol >HTML image elements embed images in documents. The src attribute contains the image URL and is mandatory.
is an empty element meaning
it should not have a closing tag.
< img src = "image.png" >An element can have alternative text via the alt attribute. The alternative text will be displayed if an image fails to render due to an incorrect
URL, if the image format is not supported by the browser, if the image is blocked from being displayed, or if the image has not been received from the
URL.The text will be read aloud if screen reading software is used and helps support visually impaired users by providing a text descriptor for the image
content on a webpage.
< img src = "path/to/image" alt = "text describing image" />The
< video src = "test-video.mp4" controls >
Video not supported
</ video >The document type declaration is required as the first line of an HTML document. The doctype declaration is an instruction to the browser about what type of document to expect and which version of HTML is being used, in this case it’s HTML5.
The anchor element is used to create hyperlinks in an HTML document.The hyperlinks can point to other webpages, files on the same server, a location on the same page, or any other URL via the hyperlink reference attribute, href . The href determines the location the anchor element points to.
< a href = "codecademy.com" > Visit this site </ a >The target attribute on an anchor element specifies where a hyperlink should be opened. A target value of "_blank" will tell the browser to open the hyperlink in a new tab in modern browsers, or in a new window in older browsers or if the browser has had settings changed to open hyperlinks in a new window.
< a href = "https://www.google.com" target = "_blank" > google </ a >URL paths in HTML can be absolute paths, like a full URL, for example:https://developer.mozilla.org/en-US/docs/Learn or a relative file path that linksto a local file in the same folder or on the same server, for example:./style.css
Whitespace, such as line breaks, added to an HTML document between block-level elements will generally be ignored by the browser and are not added to increase spacing on the rendered HTML page. Rather, whitespace is added for organization and easier reading of the HTML document itself.
In HTML, comments can be added between an opening .Content inside of comments will not be rendered by browsers, and are usually used to describe a part of code or provide other details.Comments can be single or multiple lines.