Backlink

A backlink is any link from an external website pointing to your site. Google's original PageRank algorithm was built on the insight that links are votes—if many reputable sites link to you, you're probably trustworthy and relevant. That core principle still holds today, making backlinks one of the most important off-page SEO factors. Not all backlinks are equal. A single link from the New York Times is worth more than 500 links from low-quality directories. What matters is the authority of the linking domain, the relevance of the linking page to your content, whether the link is dofollow or nofollow, and the anchor text used. Backlinks are earned in several ways: creating genuinely useful content that others want to reference, guest posting on relevant publications, digital PR campaigns that get press coverage, and building tools or resources that become industry references. The dark side: link schemes, paid link networks, and private blog networks (PBNs) can manipulate backlink profiles. Google's Penguin algorithm specifically targets unnatural link patterns. Getting caught can result in manual penalties that devastate rankings for months.

• 1A Forbes article linking to your case study is a high-authority backlink
• 2Getting listed in industry directories builds a diverse backlink profile