Grey hat marketing is a combination of commonly accepted SEO techniques, such as paying someone to write an article for your website, and banned practices known as "black hat marketing," such as hiding keywords in a page by making them the same color as the background. One common grey hat marketing technique is to "linkbait." Linkbaiting occurs when you write a tailor-made article in order for social bookmarking sites to link to your site. You can also pay popular social media sites to link to your site. As more sites link to your site, search engines raise your site's ranking.