Google shook up the SEO world by announcing big changes to how publishers should mark nofollow links. The changes — while beneficial to help Google understand the web — nonetheless caused confusion and raised a number of questions. We've got the answers to many of your questions here.| Moz
Discover link opportunities and monitor link building efforts with Moz Link Explorer. This free backlink checker provides easy access to Domain Authority, Page Authority, linking domains, and more in just a few clicks.| Moz
Spam Score represents the percentage of sites with similar features we've found to be penalized or banned by Google. Our machine learning model identified 27 common features among the millions of banned or penalized sites.| Moz
Domain Authority is Moz's best estimate of how well a domain will perform in organic search results. Learn how Domain Authority is calculated and why it's important to SEO.| Moz