What is a backlink?
A backlink is simply a link from one website to another. When a website links to your website, it's like a vote of confidence. It tells search engines that your website is a credible source of information. The more backlinks you have from high-quality websites, the more likely your website will rank higher in search engine results pages (SERPs).
Backlinks are essential for SEO because they help search engines discover new content and determine how well a page should rank in search results. When a website links to your content, it's essentially vouching for the quality and relevance of your page. This can help improve your website's visibility and organic traffic.

What is Domain Authority?
Domain Authority (DA) is a search engine ranking score developed by Moz that predicts how likely a website will rank on search engine result pages (SERPs). DA scores range from one to 100, with higher scores corresponding to a more remarkable ability to rank. Domain Authority is calculated by evaluating linking root domains, the number of total links, and other factors.
It's important to note that Domain Authority is a relative metric. This means that it's best used to compare the "strength" of one site to another. For example, a website with a DA of 50 will likely rank higher than one with a DA of 30.