Link popularity is the measure of links pointing to your website and is meant to be a measure of the best websites. Theoretically those websites that have the most links pointing to them must be important and thus worth the visit.
Search engines don't just look at the content of your website to determine if you are a match for a search. They also look at the number, relevancy and quality of outside websites that can validate, by linking, that you are a good match. Search engines have also begun to rank the importance of the sites that link to you.
Many online marketing specialists believe that link popularity is simply obtaining as many links as possible. It's not just the raw number of links that matters. The quality of those links counts. You will get better results in search engines if you have link popularity from sites with good PR and closer theme fit. Getting links from FFA (Free For All) links, link farms, link services, automatic link generators, doorway pages, spamming with keyword text are a waste of time and money. In some cases the use of these methods will get you banned from a given Search Engine.

Submitting to Directories   Directories are fundamental for building link popularity and targeted traffic. Directories are broken down into specific categorical topics followed by subtopics. A quality link from a major directory carries more significance and weight than scores of links from websites that aren't applicable to your website, product or service. It is also important to get links from topic specific or niche directories. These are websites that are dedicated to news and information that is an exact counterpart for what you provide online. If you have a website that deals with generator parts, being listed on sites that focus on generator is very important.     Exchanging links through associates and vendors   One of the most overlooked spots for building link popularity is links from partners and vendors for your business. Because you already have a business association with these companies or individuals, you are more likely to be able to request and receive a link from their website.     Sensible Internal Link   Internal linking also plays a vital role. A well-constructed and coded linking structure will help search engine spiders steer your site. This will eventually aid search engine users locate your content.     Exchanging links with other webmasters   Asking another webmaster for a reciprocal link is standard practice on the Internet related to yours, but not with the direct competitors. Webmasters have been asking other webmasters for reciprocal links since the beginnings of the Internet. Before you can send a reciprocal link request, you need to explore their web site to decide if you want to include them in your link directory, if it fits your criterion, create a Links page in your site, and add the URLs of these sites to the Links page. Then, send an email to these webmasters, introduce yourself and your website, DO NOT commercialize your email in any way, personalize your email message, personal comment should prove beyond any shadow of a doubt that you personally visited their website.     Posting Articles   It is advantageous to write unique articles and getting it published in article directories or portals. The articles published can be permitted to be republished with the URL in the resource box. This activity, along with aiding your link popularity thematically, will also improve your image and PR.