A noindex tag is a meta tag that instructs search engine crawlers to intentionally disregard a specific web page from being included in its indexing process. This attribute ensures that the page will not appear in the search results.
You can implement the noindex meta tag either within the section of a page’s HTML or via its HTTP response header. However, a page must be successfully accessible to crawlers for them to note and honor this command. Therefore, if you wish to use the noindex tag, you must verify that the page is not blocked by a robots.txt file.
It is advisable to use noindex tags for necessary web pages that have no logical reason to appear in public search results.
For example, pages such as thank you pages, internal admin login portals, or consolidated author archives may be functionally necessary for your site’s operation, but no user would need to search for them on Google.