Explain the concept of backlinks and their role in SEO

Backlinks are links from one website to another. They are essential in SEO because search engines like Google consider them as votes of confidence for a website's credibility and authority. High-quality backlinks from reputable websites can significantly improve a site's search engine ranking. However, it's important that these backlinks come from trustworthy sources, as low-quality or spammy backlinks can harm a website's SEO.