A Title tag is also part of HTML coding, it's the title that's placed at the top of a web page, this also what search engines often use as the title of a listing in the search results.

Title tag is the important element for SEO

A title tag is an HTML element that specifies the title of a web page. Title tags are displayed on search engine results pages (SERPs) as the clickable headline for a given result, and are important for usability, SEO, and social sharing.

A title tag is technically a piece of HTML code used to tell search engines what’s the ‘name’ of your page Because it’s the first thing that they see, the title tag is a very strong signal for search bots to understand what the page is all about.