Meta are element used to provide data or content about a HTML tag to summarize a web page’s content and not displayed on the page. Meta elements often be used to specify page keywords, author information, description and any other meta data attributes. Meta elements can be used to emulate the use of HTTP response like 301 redirect or embed additional meta data in your page.
Mainly, meta data can be used by browsers, search engine or other web services. The tags are defined within tag.
Example 1 - Define keywords for search engines:
<meta name="keywords" content="Ruby on Rails, Web Development, Web Design">
Example 2 - Define a description of your web page:
<meta name="description" content="Ruby on Rails Development Company | 41studio">
Example 3 - Define the author of a page:
<meta name="author" content="Irfan Fadilah">
Example 4 - Refresh document every 60 seconds:
<meta http-equiv="refresh" content="60">
Meta Elements in Search Engine
I still suggest you to keep using meta tags even when Google have announce the meta tags will not affect your ranking anymore, because they still support meta descriptions and include them as snippets in SERP. For example, meta description are still useful for search engine display the result. Here’s the commonly used tags for SEO :
Meta Elements - Description Example of 41studio.com
This is the description about the page, highly recommended to contains no more than 150 characters including spaces.
<meta name="keywords" content="Your Page Description Here”>
Tell what natural language the website is written in (e.g. English, Spanish or French). This is best if you aim for local audience.
<meta name="language" content="english">
To specify the keywords in that page, this is not used in Google Search ranking factors anymore, but there’s issue that some search engines are still use this data.
<meta name="keywords" content="keyword 1, keyword 2, keyword 3">
You can read the full explanation about usage of meta elements for SEO here