As a brand, you need to know the difference between the three and how to avoid being penalised and blacklisted by search engines with your SEO approach.

To achieve your business goals, it’s important to lay out your roadmap and it’s even more important to implement it on your website. One such trending and most effective strategy is SEO. Search Engine Optimization can help you to get better reach and engagement and help your website rank better in the top SERPs(Search Engine Result Pages).
SEO is used to help a brand rank higher on search result pages so that a user looking for relevant online content lands on the brand's website. Misusing SEO to manipulate algorithms and rank higher just for pageviews can damage your website and lead to ‘Manual Action.’
Many marketers prolifically used black hat SEO tactics to rank websites. However, times have changed. Google’s algorithms were less advanced back then, especially when it came to identifying web spam. But now, the algorithms used by the major search engines like Google, Yahoo! and Bing have evolved to combat obvious and unethical manipulations of search results algorithms.
Black hat SEO is the false practice, white hat SEO is the good practice, and grey hat SEO is the combination of good and bad practice. Below is how they affect your overall performance:
Black Hat SEO
Black hat SEO practice poses a risk against search engine guidelines and is used to get a site ranked higher in search results. These unethical tactics manipulate the user's search queries and often end up getting penalised by search engines. Black hat techniques include keyword stuffing, cloaking, paid links, sneaky redirects and using private link networks(backlinking). 

These false practices can lead to being wiped out completely from search results or gaining a lower position in search engine rankings. This means your website will be blacklisted, shadow banned, gain less traffic and ultimately, fewer customers. While you may see short-term gains from black hat SEO, it isn’t beneficial in the long run. Research your niche and use the best practices of Google webmaster policy to create quality content. It will take time to see visible results but it’s still better than being penalised.  
Grey Hat SEO
According to SEO Consultant John Andrews, Grey Hat SEO is not something between Black Hat and White Hat, but rather “the practice of tactics/techniques which remain ill-defined by published material coming out of Google, and for which reasonable people could disagree on how the tactics support or contrast with the spirit of Google’s published guidelines.”
Grey hat SEO straddles the border between black hat and white hat SEO. Grey hat tactics aren't usually stated as prohibited activities in webmaster rules, but they are suspect. Grey hat SEO changes over time; what’s considered a grey hat one year could be classified as a black or white hat the next year. Many grey hat tactics have evolved into black hat tactics as search engines have become more discerning.
White Hat SEO 
White hat SEO is the righteous one and means following the “rules.” You use only ethical tactics and follow search engine guidelines. These are one of the best practices you can use for your website. Even though it is a slow process it gives better results and is more long-term oriented. Using the right keywords, offering quality content and services, using descriptive keyword-rich meta tags, fast site loading times, mobile-friendliness, optimising good links, and technical SEO are some of the methods you can use as a white hat SEO practice.
Quick wrap-up
The only SEO rules we must follow are the ones given by search engines. They own the platforms you use and as a webmaster, you must follow guidelines in good faith. Search engines set the conditions for any website to stay. Since search engine algorithms have become more sophisticated over time, black hat SEO should be avoided at all costs. Grey hat SEO must be avoided too. What’s unethical is unethical and your manual action reconsideration won’t be taken seriously if you claim that you have made only 50% mistakes to manipulate search rankings. White hat SEO is a far better way to optimise your website. It's a more ethical strategy that adheres to search engines' guidelines. White hat SEO entails producing high-quality content and providing a better user experience for website visitors.
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