One of the most important factors in search engine results is Link Popularity. This is what you would call the tie breaker, If one webpage has the same keywords you do the same amount of time as you, then the search engines will use link popularity as the tie breaker. Let's say your keywords were domain name & another webpage uses domain name as their keyword and your domain name had say 100 links to that domain name, if the other domain name had say 150 links then the other site would have be above you in the search results. Now if the other site had say 10,000 links he could have way less of the same keyword you do and still rank way higher.
Who Links To You & Who You Link To Are Very Important
The Links on the in-coming side, that is from other sites (Inbound) and links out going should be somehow related to the content of the page they are directed to or from.
You Will Also Have Temporary & Long Term Links
Temporary links are links created when a search say google is showing your website in search results. These Links are to quick to get indexed. Where A long term link is on a website. What you need is long term links. Links are link gold to the search engines and they show their worth in the search results.
If your looking to gain link popularity then you will need to create links. A link is only worth link popularity if it's indexed by a search engine. If I gain a link on a webpage that was say in google it would count toward link popularity. If the link was on A page that wasn't indexed by google then the link is worthless to google but that link might be indexed in yahoo, be that the case it would count towards link popularity in yahoo.
Now a link form a website that's been around for a long time is worth more than a link that's brand new. Think of a link as A vote of trust that a website give to another site.
A Websites Webpage - PageRank
PageRank is something google give to a webpage to tell how important a website is. It is based off a scale of 1-10 (ten being the highest). A link from a webpage with a high page rank is worth alot more than just one link. A link from a webpage with a rank 5 is worth 100 normal links or could be. It's said that a links worth is based on the page rank divided by how many links are on the page. So A rank 5 page with 150 links is worth less an say a page with 30 links.
Don't Link To Bad Websites
Who you link to makes a Diffence. Link form a page that's relavent to your page give you a boost in search results. Linking to sites that use unethecal pratices for their website can be bad. linking to bad sites can be like catching a cold. If you link to one of those site it some search engines could drop your page rank & even ban you from their index. Once this happens your Finished and you will have to start all over from the beginning. Link farm is the worst & linking to them will get you banned really fast. Don't link to bad sites.
FFA Type Of Sites Will Not Help Link Popularity
Submitting to A FFA type of site will do you no good for the links themselves. These sites are only offer short term links and should be used for traffic considerations only, as is the volume of e-mail associated with them. For productivity purposes they are almost useless today for generation of sales anyway. This is due to the failure of proper regulation by the site owners, as many allow spamming or rotate the links to quickly to serve any purpose.