Black hat strategies are the poisoned chalice of SEO. The term refers to strategies that get results quickly but through dishonest means. Some examples are keyword stuffing with invisible text, purchasing hundreds of backlinks that have no relevance to your website, and mass publishing poor-quality content.
These strategies provide results initially through trickery, but the Google Algorithm gets better every day at detecting these dodgy tactics. As a result, websites using black hat SEO strategies are quickly penalised by being dropped right down in the search rankings or even permanently banned.
On the other hand, white hat SEO is the sustainable, honest way to build your website. The main goal is to create a website that internet users find genuinely helpful and informative through legitimate tactics, unique content, and hard work.