For improving the Web page rank of you blog, be careful to make a link exchange with a site which is not under your blog niche, So don’t get caught up your blog in a link farm scam. A link farm is a large group of Web pages created for the sole purpose of trying to trick search engines into increasing the Web page’s ranking. While it is perfectly legitimate to exchange links with other Web sites, it is not at all proper to set up Web pages just so you can establish links with them to your real Web site.

There are other resources on this topic read them and make your blog safe and sound.

Link farm definition from From Wikipedia:

On the World Wide Web, a link farm is any group of web sites that all hyperlink to every other site in the group. Although some link farms can be created by hand, most are created through automated programs and services. A link farm is a form of spamming the index of a search engine (sometimes called spamdexing or spamexing). Other link exchange systems are designed to allow individual websites to selectively exchange links with other relevant websites and are not considered a form of spamdexing.
Search engines require ways to confirm page relevancy. A known method is to examine for one-way links coming directly from relevant websites. The process of building links should not be confused with being listed on link farms, as the latter requires reciprocal return links, which often renders the overall backlink advantage useless. This is due to oscillation, causing confusion over which is the vendor site and which is the promoting site. Read More

Promotion Tip: Link Farms Grow Spam

What is Link farm & Why should you Avoid it!

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Avoid Link Farms & Get Better Rankings