HTML5 (Current Standard):
There are around 110+ elements/tags defined in HTML5 including:
Structural elements like <header>, <footer>, <nav>, <article>, <section>, <aside>
Text content elements like <h1> to <h6>, <p>, <strong>, <em>
Form-related elements like <form>, <input>, <select>, <textarea>
Multimedia elements like <video>, <audio>, <canvas>, <svg>
Semantic elements like <main>, <figure>, <figcaption>, <details>, <summary>
Interactive elements like <button>, <a>, <label>
Metadata elements like <meta>, <link>, <style>, <script>
Document sections like <body>, <head>, <html>
This list isn't exhaustive, and there are also many obsolete tags from older versions of HTML that might still be found in legacy code but are not recommended for use in modern websites.
If you're asking specifically about how many tags are used in a particular HTML document, that would depend on the complexity and purpose of the document. Each page can use a subset of these tags based on its content and structure needs.
In HTML, elements are categorized into two main types based on how they affect the layout of a webpage: inline and block-level elements. Here's a breakdown of each:
Inline Elements
Definition: Inline elements only occupy the space bounded by the tags defining the element. They don't start on a new line and only take up as much width as necessary. They flow within the content of their parent element, affecting the text or content around them without breaking the flow of text.
Examples:
<a> - Anchor for hyperlinks
<span> - Generic inline container for phrasing content
<strong>, <em> - for strong emphasis and italics, respectively
<img> - Embedded image (although it can behave like a block element with CSS)
<button> - Inline unless CSS specifies otherwise
Behavior:
You can't set width or height on inline elements (though you can set padding, margin, border which can affect the size indirectly).
They do not force a line break before or after them.
Block-level Elements
Definition: Block-level elements start (and sometimes end) on a new line. They occupy the full width available unless specified otherwise, and they can have margins, padding, and borders that push other elements away from them.
Examples:
<div> - Generic container for flow content
<p> - Paragraph
<h1> to <h6> - Headings
<ul>, <ol>, <li> - Unordered, ordered lists, and list items
<form> - Form container
<header>, <footer>, <section>, <article>, <nav> - Semantic structural elements
Behavior:
By default, they take up the full width of the container and start on a new line.
You can set width and height directly on block elements.
They can contain other block-level or inline elements.