Nofollow, rel=nofollow

Nofollow s a knd of HTML attrbutes that defnes hyperlnk relatonshp betwe the lnkng page and the lnked page.

1. t can be used wh you don’t want your lnks to nce the targeted ste’s rankngs by search gnes. That s, the denaton of that hyperlnk won’t be gv any tonal weght or ct n search result rankngs.

“From now on, wh Google sees the attrbute (rel=”nofollow”) on hyperlnks, those lnks won’t get any ct wh we rank webstes n our search results.”
Post on Google Blog on 2005-01-18

Not only Google but Yahoo! and MSN Search have agreed to ths new hyperlnk relatonshp attrbute.

2. Ths also prevs lnk spammers from spammng blogs and web forums by pong lnks n comms and sgnatures.

WordPress seems to ths attrbute by default to the lnks left n comms.

3. You can use ths attrbute on some of the lnks wthn your webste to maxmze lnk values to mportant cont pages.

For example, let’s say that you have a ste sellng runnng sneakers. From the page, there are two lnks wthn the ste. One s a lnk to About Us page and the other s a lnk to How To Choose Runnng Sneakers page. Each of these pages gets 50% of the rank value of the page n Google, but you don’t really care about how well the About Us page ranks n search gnes. n ths case, you can the rel=nofollow attrbute to the About Us lnk. Ths wll gve the full score of the page rank value to the second page whch contans mportant cont for your ste.

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