Everywhere you hear nowadays of links. In the area of the search engine optimization they appear mostly under the keyword "backlink", but the topics linkbuilding or linking are important, too. But what is a backlink actually?
A backlink is a linking from another page to the own website. It does not matter if this link shows to the homepage or to a subpage. In the latter case you speak mostly of deeplinks.
Backlinks play an important role in the area of search engine optimization, especially according to the evaluation of a website by search engines. Search engines are obligated to use objective criteria for this evaluation. One of those criteria is the number and quality of the existing backlinks, that show to a page. In the subarea of the offpage search engine optimization the SEO's mainly work for building a link structure as natural and continuous as possible. So the website appears in a good light for the search engines.
Basically it is easy to receive any backlinks. But the challenge is that you need especially topic relevant and high-quality links for your ranking in the search engines. Links from banner farms or substandard pages would be counterproductive for the goal of the offpage optimization.
If you always present up to date and useful content on your page, you will receive backlinks by and by automatically. But this takes a lot of time. It is easier to buy text links for the linkbuilding. If you search in the database of Linkmads, you will find topic related links to rent. So you may receive backlinks without any waiting periods and the costs always stay transparently.