The Head Section

Tags which are important in head section of your web page,

<meta http-equiv="content-type" content="text/html; charset=UTF-8">  
<meta http-equiv="content-language" content="en-us">
 

<meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1"> 

<meta http-equiv="Cache-control" content="public">
 

<meta name="robots" content="all"/>
 

<meta name="application-name" content="Website Name"/>
<link rel="canonical" href="current canonical url" />
<link rel="shortcut icon" href="shortcut icon"/>  
 

<meta name="copyright" content="Copyright info"/>
<meta name="author" content="Author Info"/>

<meta name="viewport" content="width=device-width, initial-scale=1.0">
 

SEO Fields 
<title>Your Website title</title>  

<meta name="keywords" content="keywords"/>
<meta name="description" content="Page description"/>
<meta property="fb:page_id" content="fb page id" />
 

<!-- dns-prefetch -->
<meta http-equiv="x-dns-prefetch-control" content="on">
<link href="url for your cds" rel="dns-prefetch" />
 

<!-- apple app icons -->
<link rel="apple-touch-icon" sizes="57x57" href="/apple-touch-icon-57x57.png" />
<link rel="apple-touch-icon" sizes="72x72" href="/apple-touch-icon-72x72.png" />
<link rel="apple-touch-icon" sizes="114x114" href="/apple-touch-icon-114x114.png" />
<link rel="apple-touch-icon" sizes="144x144" href="/apple-touch-icon-144x144.png" />
<link rel="apple-touch-icon" href="/apple-touch-icon-57x57.png" /> 

<!-- schema.org -->
<meta itemprop="name" content="Page Name">
<meta itemprop="description" content="Page description">
<meta itemprop="image" content="Logo image/ Image to be shared">
 

<!-- twitter card -->
<meta name="twitter:card" content="Card Name">
<meta name="twitter:url" content="Card URL">
<meta name="twitter:description" content="Card Description">
<meta name="twitter:title" content="Card Title">
<meta name="twitter:image" content="Image to share"> 

<!-- facebook open graph -->
<meta property="og:title" content="Open graph title"/>
<meta property="og:description" content="page description"/>
<meta property="og:type" content="type of content"/>
<meta property="og:image" content="Image to be share"/>
<meta property="og:site_name" content="Site name"/>    
<meta property="og:url" content="Site url"/>