Some SEO's will tell you that reciprocal linking is good, when done with a site that's ranked higher than you and is also related to your site's theme. Others will say that reciprocal linking has outlived it's coarse. If you choose to trade links, here's a few things to consider:The point of obtaining back-links is to help your search engine rank. Every link to your site is like a vote for your site. If it's a one way link, from them to you, even better! The quality of the back-link is also important. If an authoritive site like Microsoft were to link to your site, it would be considered a very important "vote," and would surely outway back-links from many other sites. But what if your back-link isn't real?There are website owners and directories out there who are willing and eager to trade links with you. But beware, because what they're really trying to do is create a one way link; from your site to theirs! The way they pull this off is by camouflaging your link, rendering it invisible to search engines. Search engines ignore JavaScript, so writing a short script for your link is common. Another method is using Google's new invention: The rel="nofollow" attribute. Google and many other search engines have partenered with Blogging sites to combat comment spam (the practice of dumping your link in a blog to try to improve your page rank). Links posted in most blogs contain the "nofollow" attribute, directing the search engines to ignore it. Well, website owners are catching on, and it's possible that your reciprocal link contains the same attribute.A third way of hiding your link from search engine's is by using a "re-direct" script. Instead of your link's URL taking you directly to your site, your link's address is actually another file located within the same site. Once the browser reaches this page, it then reads a re-direct script and finally takes you to your page. Because your link was never actually a link to your site, and because search engines ignore JavaScript, your URL is never read or recognized by the web crawler, rendering your link useless for Page Rank purposes. "But what if the re-directing page is accompanied by a text link with my URL intact," you ask. One of two things could be possible:1) The link is helping your Page Rank.2) The re-directing page with your link is included in the site's robots.txt file. A robots.txt file instructs search engine crawlers to avoid cerain web pages and sub-folders. It's possible that any page where your link lives is purposely avoided by web crawlers using this method. To see if the page where your link lives is included in the site's robot.txt file, simply type "http://www.sample-url.com/robots.txt" into your browser's address bar. If you see your link's subfolder or web page listed after the word, "disallow," then your trading partner has pulled a fast one on you."But why would website owners want to do disguise my link?" you ask. Two reasons:1) A one-way link is rated higher than a reciprocal link.2) Trading links with a website that is ranked lower than your own can hurt your page rank, but an inbound link from any site is always positive (as long as the site is not considered a "bad neighborhood").There is software out there that can check for valid links. Get hold of it, and you can check your back-links with ease. Another (and more tedious) way is to manually check the HTML code. Even beginners can do this. Just click your browser's "View Source" option, and select "Find" or "Search." Enter your url, and the search tool will automatically scroll the page for your query. If found, be sure to check if it is a JavaScript link or if the rel="nofollow" attribute is present. If not found, then it's likely your link partner is hiding your link's url with a re-direct script. Hopefully, you'll find your link unscathed, helping to increase your Page Rank.Generating back-links is not easy work. If you've read about SEO, you know that their essential for Google in particular. But if you decide to trade links, make sure you're getting your end of the bargain!