Meta Description is an HTML tag that gives a short description of the content of the web page and is of 160-character snippet which appears below URL. This short description helps Google and another webmaster to display our content on the webpage. This snippet acts as an ad copy of the content and gives a clear idea of the content of the site.
Highlighting the keyword in the page’s meta description that the page is targeting increases the search clicks on the webpage. In the early days, the meta description was an important optimization point in SEO.
If you think that meta description helps in the ranking, then it’s not completely true. A strong keyword in meta description drives click-through rate from Search Engine Results Page(SERP) which helps in SEO ranking of the webpage and avoids a high bounce rate. Increased CTR results in more traffic to the site. So it’s not the ranking factor but its conversion factor in SEO. This information serves as a snippet for the text shown to searches in response to a query.
In simple words Meta Description = Text Ads for your content
Relevant keywords and proper optimization in meta description improve user engagement which is equal to high conversions. Increased CTR and traffic cause google to promote your website.
Is the Meta keyword tag necessary for web pages?
Ignoring meta keyword tag in SEO is a wrong practice as the search engine gives value to it. All tags available in SEO should be utilized as it comes under the practice of White Hat. Adding alternative words, synonyms, and misspelling to meta tags is the best method to increase the click-through rate.