What are paid links?

What are paid links?

Google’s definition of a paid link, is “exchanging money for links, or posts that contain links; exchanging goods or services for links; or sending someone a ‘free’ product in exchange for them writing about it and including a link.”

Paid links are a dangerous SEO strategy designed to artificially boost your ranking by paying other sites to link to your content.
Even sponsored guest posts and paid reviews are considered paid links.
Today, the rise of organic link building and content marketing has more or less nullified the need for buying links in the SEO industry at large.