What exactly is a Quality Backlink ?

A Quality Backlink is a link that has clout and power. It's a link that has a pagerank which can flow to your site. They're links that are DO-FOLLOW and come from a page with limited outbound links.

Links that don't meet the criteria are;
long listings
FFA Lists
A 0 rank page
Alexa Rank in the millions
A site with no links from the outside to them.

Often you'll see some blog posting services where they'll post your link or to a number of blogs, or they'll post a blog comment for you on a number of sites, MOST times these sites are owned by the service you're purchasing from and they could be about anything. A blog that has details about car repair and then for some odd reason links off to "the best pet toy ever" is highly suspicious of being a PAID link, and wouldn't even get a second look by search engines.

Quality over quantity - just like food! You want to link from a reliable site, one who has followers or at least the same field that your busienss/site is in.

A quality backlink is a links that points to a site using the suitable keywords or keyword phrase, and from a related site that of similar content as the Web site its pointing to.

Now I'm hungry - for more (quality) backlinks.

Obviously, the search engines are looking for relevancy - of search queries to results. And to some extend, I am beginning to see improvements in their rankings.

Quality of the links could be evaluated from several aspects and routes; they could include which anchors have been used as well as the relevancy of the linking pages to the sites which are receiving them actually. The age of linking sites too is very important because the older they are the better and no wonder some web directories which have been operating since a decade ago could be great links sources.

A quality backlink is one that can give you a proper link value in the eyes of the search engines. Its a link from page that has a good page-rank, it has a good value in sites and has no relation to the traffic rankings like alexa etc.

It should be crawled and indexed easily, and should be relevant to the topic of the linking site.
As its always observed, a few quality links are better than hundreds of low-quality spammy links to your website.

Quality Backlink is a natural incoming link for a site from the most relavant site. That means the link that automatically we get without any link exchange. The site should be thematically related.
If you can get backlinks from the pages which has higher PR, less outbound links and proper anchor text that will be a Quality Backlink.

All you need is a few friends in high places ;-)

The most important factor is the page rank of the web page giving the backlink. Backlinks from highly ranked sites are of good quality. Another factor is the subject of the pages which are linked by a backlink. If both sites are discussing the same topic, the backlink is relevant and of good quality.

quality backlink is more important to get best pr in search engine...

Quality deals with relevancy!

Backlinks, or inbound links, are one of the single-most important factors in SEO. And quality is the most important factor in backlinks (not quantity). Here’s what you should look at when determining the value of a backlink.

Anchor text – does the anchor text include your targeted keywords?
Relevance – How closely related to your site is the site/page the backlink is on?
Other Links- How many other outbound links are on the page that links to your site? If there are 59 other links, the link to your site will not be as valuable as if it would be if there were only 2 other outbound links.
Domain age – Google especially places extra significance on links from older domains.
Permanence – Your backlink should be static / permanent to offer good SEO value.
Page Prominence- How prominent on the site is the page that links to your site? A page buried 5 clicks from the homepage will not likely give you a very valuable link.
Link popularity – How many backlinks does the site / page that links to your site have? The more quality backlinks the site has, the higher quality the link will be.
Other Links – Are the other links on the page related to your site?
Site Traffic – How popular is the site that links to your site?

There are few points which can add a value to the Backlink,

The age of the domain.
The PR of the backlink giving page
dofollow
OBL : It should be less

Hello,

A quality back links is with better page rank directories submission and keywords research to your links thats it.