What does mean by quality backlinks?
Quality backlinks are those links which point to your website and the website has quality and unique contents, if you get backlinks from those websites which violate copyright and has poor quality contents, Google will notice it and penalize your website.
What are the relevant backlinks?
Relevant links are those which come from your niche for example, if your blog is about SEO and the links are coming from a travel blog, food blog or fashion these are not relevant backlinks for your blog.
How to build quality and relevant backlinks?
There are many ways, but I will describe three popular ways to build backlinks.
1. Posting Comments- This is the first method that comes in mind read an article an do not forget to post a valuable comment, this also drives traffic to your website because if somebody sees your website link he will click and go on your website.
2. Guest Posting- You can write an article and instead of posting on your website post on the website of your own niche and invites for guest posting and provide also do follow link and this is a very good way to create backlinks and drive traffic to your website.
3. Directory Submission- This is also another way to create backlinks, many websites provide the way to submit your link and post title search such of the directory and put your article link and title and that will be a backlink for your website.