In connection with ranking, all large search engines, in particular Google, nowadays take into account not only page content (e.g. key word density, title tags etc.) or domain factors (e.g. age) but first and foremost inbound backlinks. The theory behind this is as follows: the more inbound links a page has, the greater the probability that the page contains "valuable" contents.

The Google algorithm not only evaluates the number of links that link to a webpage, but also their quality, which can essentially be measured in three ways:

· Is the page that links to your page thematically related to your page?
· How popular is the page that links to your page? (How many inbound links does it have? How high is its PageRank? What is the site's ranking on Google?)
· How many outbound (external) links does the page have that links to your page?
The help section in the customer account contains a "Link Buying Guide" which provides comprehensive information and valuable tips about the procedure for purchasing links. 
Here is some further information about the individual factors:

Link texts
For powerful search engines such as Google, the link texts that are used to link to another page are very important for the ranking position of the page. Since a link is seen as a "recommendation" for a webpage, many inbound links influence the ranking positively. The links with a text that contains precisely the keywords for which a website was optimized are particularly important. In addition, the search engine rates the content relevance of the linked page positively. Hence, for example, the website of a car insurance company profits particularly from inbound links that contain the words "car insurance" in the visible link text. However, you should make sure to vary the relevant link texts and make them look natural when buying backlinks.

PageRank
The PageRank is the value with which Google rates a website on the basis of the number and the weighting of its inbound links, and forms the core of this search engine. This value is represented as a number between 0 and 10. Whereas a high PageRank also used to be clearly associated with a high ranking position, this association has no longer been valid to the full extent since the beginning of 2004 and has recently been further restricted.

The first criterion to consider when purchasing backlinks is the relevance of the link website to the target site. It is really not worth buying backlinks based on PageRank only. There are many factors that contribute to the ranking and simply going by PageRank is no sufficient focus anymore.
This is also the reason why there is hardly a relation between a high PageRank and the ranking on Google anymore.

Content relevance of the website / relevant keywords
Only bookings with a clear thematic connection between the buyer's URL and the seller's URL make clear sense. Content-irrelevant links no longer lead to the desired results. With linking, the content relevance of two webpages is much more important than PageRank. Content relevance means that there is a relationship between the target URL and the offer URL in terms of content. This does not mean that the target URL must deal with exactly the same topic, but merely that some reference can be found between the two pages. At teliad you will specifically see keywords that are relevant for the offered website. Therefor you can determine the topic area of a webpage very accurately. Also we will display the ranking strength of a URL for all keywords.

RankingScore
The RankingScore states how a given URL ranks on Google, respectively, how significant a site is on Google. The RankingScore does not evaluate an entire domain but each URL/subpage separately. Thus, the RankingScore helps, among other things, with the evaluation of the possible quality and strength of a backlink from this specific URL.

Link popularity
This refers to the quantity of inbound links to a website. Since the link popularity represents a decisive ranking criterion for many search engines, it can be assumed that if a website has a high link popularity, its placement in the search engines will improve.

Domain popularity
This additional ranking criterion describes the number of links that link to a website from different domains. As opposed to link popularity, only one single link from domain X to domain Y is accounted for, even if, for example, numerous additional links from domain X to domain Y exist. This also applies to sub-pages.

Backlinks set on a sustained basis
For Google it is very important that backlinks are set for long periods. Frequent changes in the backlink structure, i.e. a constant, unnatural changing of backlinks is more likely to be rated negatively by Google.

However, numerous other factors are also decisive for search engine ranking. There are plenty of pages and forums on the web that are intensively concerned with this subject and contain numerous tips and information. These different factors must be taken into account depending on the size of the website and the importance of the search engine ranking. Whereas two or three content-relevant link texts from pages with a lower PageRank suffice for a small website with a search term for which there is little competition, complex portals with hotly-contested search terms require significantly more inbound links of the highest quality, respectively, a long term linking strategy.