I have red alot about Dofollow links, can someone explain to me what they are?

One of the tricky things when running a forum or comments on your blog, is that spammers might target your blog to generate backlinks to your site.

For SEO purposes, the sites your site links to make a difference. If you link to sites that Google considers spam (meaning, having no useful content for your users), then it will lower your rankings for that site.

Site owners complained about this, saying that they didn't always have control over what sites their site linked to.

So the search engines collaborated on a solution, and that was NOFOLLOW and DOFOLLOW.

If you want to give your users the ability to leave links but don't want to assume responsibility for that link, then you can program your site to automatically add a NOFOLLOW link to the links they provide. That way, search engines will not penalize you for linking to certain sites they consider spammy

Another application of NOFOLLOW and DOFOLLOW is link juice. If you have a page that doesn't offer any benefits in terms of SEO, you can tag the link to that page as NOFOLLOW. As a result search engines will not index that page (in theory).

It is a great way of adding content to your site (e.g. an about section) without losing keyword density.

The general rule: if a page is important in terms of SEO (meaning that you want it to rank well in the search engines) link to it normally.

If a page has only practical usages (e.g. a Terms & Conditions page) but has no value in terms of SEO link to it with NOFOLLOW. That way, that page will not compete for rankings in the search engines, instead, the more important pages will be found by your users.

It makes a small difference, but every little bit helps, especially if you are a small site.

So would you say that it's not possible or perhaps not practical to deal with each link separately?

I guess the worse case scenario is that there's an excellent link for your site on the same page as several spam links?

You can deal with each link separately. And when you write the content yourself it makes perfect sense treating each link with DOFOLLOW or NOFOLLOW at will.

But when you have a large community blogging, commenting or posting forum posts on your site, it can become hard to maintain, and then it is better to use an algorithm that tries to decide what links are spam and what links aren't.

As a general rule on this forum we treat links that are simply pasted in as NOFOLLOW, e.g. www.google.com, while link that are purposely posted using the editor (above the post box) are treated as follow (e.g. Google).

The reason behind this is that spam bots tend to post their links in this format: www.google.com and not the styled format (Google).

Spam can severely hurt a site and it is always good to code your site in such a way that no-one can take abuse.

If there is an excellent link on your site followed by some spam links, just make sure that the excellent link has the DOFOLLOW attribute and the spammy links have the NOFOLLOW attributes. Then it won't hurt.

Of course, it would be even better to have no spammy links at all.