A backlink is a hyperlink from one website to another. Backlinks are important for SEO because they can help to improve a website's search engine ranking. When a website has more high-quality backlinks pointing to it, search engines view it as more authoritative and relevant to a particular topic.

However, it's important to note that not all backlinks are created equal. Backlinks from high-quality, authoritative websites are more valuable than backlinks from low-quality or spammy websites. In fact, having too many low-quality backlinks can actually hurt a website's search engine ranking.

Overall, building high-quality backlinks is an important part of SEO, but it should be done in a natural and ethical way, rather than through manipulative tactics. Some strategies for building backlinks include creating high-quality content, guest blogging on other websites, and reaching out to other website owners to request a link.