At its most basic, a link is a way to get from one web page to another. You might have links that go from one page on your site to another, or you might have links that go from your site to other helpful sites on the web. Backlinks are links that go from another site to yours. They point back to your pages.
What's the point of making links?
From a search engine ranking point of view, links show how popular a site is. When a site links to your pages, it's saying that it thinks they're interesting enough to share with its readers. When search engine bots find a site that is linked to by a lot of other sites, they know that the site has good information and should be ranked highly.
How do you start making links back to your site?
If you write interesting content, people will probably already link to your site. But that is rarely enough to make your site competitive in search results. You should take the initiative to build backlinks.
Keep the following things in mind:
Backlinks should come from sites that are useful and have good information.
They shouldn't cost anything. Google doesn't like this kind of "black hat" approach.
Slowly add backlinks to your site. If you make them too quickly, it could look like you're trying to change the results, which could get you in trouble with the search engines.
Another way is to look for link chances that haven't been taken. Let's say that another site used your site as a reference or quoted one of your pieces without linking back to you. By setting up a Google Alert for your brand name and other branded keywords, you can keep an eye on these missed backlink opportunities and contact the site owners to ask them to link to your pages properly.
There are also other chances to link back:
Guest posting. Offer to write for the websites of other people. This can help you get more attention and links back to your site.
News stories. An online press statement can help you get more backlinks if you have something interesting to share.
Using social networks. When you use social networking sites, you not only build your reputation as an expert, but you can also get a lot of backlinks.
Any of these backlink tactics can help your site move up in the search engine rankings, but you should keep track of the results to see which ones have the most effect. Over time, a constant link-building strategy should lead to big changes in how your site ranks in search results and how many people visit it.
Get here is list of top Quality Backlink which can boost your website ranking.