What are the important meta tags I must put in my website closed

Question

There seems to be huge number of meta tags you can set. I'm guessing that some of them are more important than others.

What are the most important metatags to supply and why?

Do I even need meta tags?

Answer 1

Regular meta info 

<title>{{pageTitle}}</title>
<meta charset="utf-8"><!-- html5 version of http-equiv="Content-Type"... -->
<meta name="description" content="{{description}}">
<meta name="keywords" content="{{keywords}}">
<link rel="author" href="https://plus.google.com/{{googlePlusId}}" />
<link rel="canonical" href="{{pageUrl}}" />