Back links are an important part of most successful websites on the net and are almost essential in order to get reasonable listings on search engines. Back links are quite simply, links from other websites. As part of most search engines algorithms it is obvious to see they rely heavily largely upon the amount of quality incoming links your website has. I would like to reiterate, quality links, there are many unscrupulous link farms and link schemes that if you participate in, will get you banned from the major search engines. Search engines see links from other, usually established, websites as a mark of respect and that you probably have something to offer.
If you your website is just starting out or you are new to the world of SEO then you should know that back links are a crucial part to a website, almost as much as any content on it. With just one link to you from another indexed site you can usually get a few search engine bots visiting your site within hours instead of days, or even weeks through manual submission. Back links usually mean that you can achieve some reasonable key words in some search engines within weeks if you have a good quality site.
Armed with the above information it is easy to see how vital back links are, so now you are wondering where to get them. Well you are advised to stay away from disreputable sources like I previously mentioned but they rarely work any way, instead you should visit places like the Sitepoint Forums & WebHosting Talk where many professional webmasters can be found. It is recommended you aim to link swap with websites that have a better google page rank than yourself