Meta tags have changed since SEO beacame a common practice,but two remain critical-the page title and the meta description.The page title plays an important role in ranking but it is also important because it is the title that shows on The search results page.It must use a keyword to rank well with the google but it must also be compelling to a user to click it.The meta description plays a role in SERP as it makes the user wnt to click on search results.