There are two basic types of links and knowing the difference of each is a vital part of being a blogger as this has something to do with the link building process.
1.) NoFollow links – NoFollow links are not read by the Search Engines. This is done in the coding of the site and prevents the links from being followed (rel=”nofollow”). Some say this will stop the PR juice to leak which is being contradicted by other bloggers who says it’s not true. (You can read further details here.)
Comments and Spam. The reason why NoFollow links exists is that it cuts down the number of spammers on the site. Spammers put comments on your website or blog with their links within trying to earn backlinks and for the PR juice. If you link to these spam sites, you will also face the penalty that Google gives. Whether you lose PR or your site will not be indexed and that’s not a very nice thing, it’s like you are not existing at all.
2.) DoFollow links – Obviously opposite to DoFollow links (lol). DoFollow links let Spiders, bots and Search Engines automate part of the process. These links are the best in the link building process and everybody is crazy about it. People are most likely to click on DoFollow links and mostly DoFollowed links are good sites, legitimate, and contains more information.
Being Safe with DoFollow Links. Be careful when you link out using DoFollow links. Make sure the site that you are linking to is relevant to your site or maybe irrelevant but not a spam site.
How to Identify Links? Here’s a screenshot showing NoFollow and DoFollow links.
These highlighted links above are NoFollow.
These links above are DoFollow.
You can identify them using these toolbars that I recommend. You just have to click the circled ones so NoFollow links will be highlighted. Click picture for a closer look.
Just register to these sites and install the toolbars.