Block Elements 

A block element always begins on a new line and takes up the entire available width 


<address> <article><aside>
<blockquote> <canvas><dd>
 <div><dl><dt>
<fieldset><figcaption><figure>
<footer><form><h1>-<h6>
<header><hr><li>
<noscript><main><nav>
<ol><p><pre>
<section><table><tfoot>
<ul><video>

Example:

<div>Hello</div>
<p>World!</p>

Output:

Hello
World!


Inline Elements

An inline element does not start on a new line and only occupies the necessary width.

 <a>  <abbr> <acronym>
  <b><bdo>  <big>
 <br> <button>  <cite>
 <code><dfn> <em>
<i><img> <input>
<kbd> <label> <map>
 <object> <output> <q>
<samp> <script><select>
  <small> <span> <strong>
<sub> <sup><textarea>
<time> <tt> <var>

Example:

<select>Hello</select>
<span>World!</span>

Output:

Hello World!