Cover-up, also known as cloaking, is a search engine optimization (SEO) technique that involves presenting different content or URLs to human users and search engines. It is considered a violation of Google's Webmaster Guidelines because it provides users with different results than expected. Search engines strongly discourage cloaking and will penalize and even de-index a website if they catch it using cover-up techniques. Some webmasters and programmers mistakenly think that they need to use cloaking to protect the source code of their website.
However, search engines don't care why you choose to use cover-up, they just see its use as a pattern of deception and will penalize you accordingly. Cover-up is an attempt to distort search engine rankings by creating deceptive content. It is an illegal practice and is considered a black hat SEO technique. Black hat SEO techniques are shortcuts that don't follow search engine guidelines and aren't ethical. These practices are meant to deceive both search engines and users by providing them with something that is not relevant and claiming that it is worthwhile. Cover-up is a part of spamdexing techniques that attempts to trick the search engine into giving a site higher ranks.
It is a search engine optimization technique in which content presented to the search engine spider is manipulated. The content presented in the user's browser is different from the content that is presented to the search engine. Now, it's true that if you cloak in the wrong way, with the wrong intention, Google (and the other search engines) can remove you from their index, and if you do it in an atrocious way, they certainly will. In such cases, webmasters don't redesign the website for SEO; they hide the content to meet SEO guidelines. It's called “cloaking” because it involves hiding the content people see and replacing it with content designed to rank better on search engine results pages (SERP). In this SEO cloaking technique, users are identified by the HTTP_REFERER header to send them covert or non-covert content. Because, according to Google's search console, central cloaking is considered a violation of the guidelines for webmasters.
Most search engines now disapprove of the practice of cloaking and will penalize websites they find that they use cloaking as a method of obtaining better search rankings. On a cloaked page, when bots crawl to index it, they find content that is highly optimized for ranking factors. Black hat SEO cloaking is a technique that can help catapult your website to appear in the best SERP results. Cloaking is done to avoid search engine ranking factors and get higher rankings on search result pages faster. Under cloaking, the website server is specifically programmed to offer different content to search engines compared to what it offers to its regular users. Cloaking is an unethical SEO practice, also known as “Black Hat”, which involves deceiving search engines (crawlers) by directing them to web pages that are not associated with the site's domain. It is advisable to avoid all the SEO cloaking techniques mentioned above to keep your website from being banned or blacklisted by Google or other search engines. Websites that use cloaking can display a highly optimized version of their content to crawler robots, while showing a substandard version or a page full of graphics to users. To stay safe from penalties from Google or other search engines, webmasters have two options: A) Have a great brand that Google won't get mad at for more than a day or two if you cross the line; OR B) Do the cloaking in a completely white way with a positive intention for users and engines.
This is an SEO cloaking technique in which contents are served by identifying the user's accept-language HTTP header.