i think you want to ask " how useful white hat and black hat SEO techniques are?" well it depends, if you want a solid long term solution for your online business or website you would obviously go for white hat seo techniques to grow your business in search engine result pages. Black hat seo will only lead to a disaster so take my advice and go only after white-hat SEO methods.
white hat seo is always good for your site. this can save your site from get penalize. but black hat seo is not good for seo as it is forbidden to search engines. black hat seo contains duplicate contents,tactics which violate search engines rules too.
Black hat SEO is the type of technique which is used by people very falsely to get into the ranking while white hat SEO is the one for getting your website on a very good ranking by your own skills.
If you want long term success, then use white hat seo techniques. If you want fast results and want to risk being penalized by google, then go ahead and use black hat techniques. The fact us black hat techniques are deceiving, google does not like them, and you may end up losing money in the process if your site is penalized.
I'm not going to go through a list, but black hat techniques include things like keyword stuffing in the title tag, description tag, h1, and page content. Invisible text is another black hat technique. They might get fast results, but they're just bad in the long run. If you use these techniques, you cant really complain if google penalizes you.
You should always stick to whitehat techniques for seo and anything to do with your online business. That is the ONLY way you will have long term success. If Google thinks you are doing anything shady they can make your sites disappear in an instant, and then there goes all of your money!
White hat SEO is ethical SEO for getting long term results. Black hat SEO is unethical way of promoting your website and it will help you to get banned from the search engines
White hat method is the backlinks or search results that you get thru with off page optimize which can meet the real tactics of the Search Engine, the vice versa is Black hat method.