WordPress is considered one of the most powerful blogging system on the net, but that doesn’t mean it do not have any drawbacks while using it. From the seo point of view it has a big drawback of duplicate content issue, unfortunately wordpress has not evolved enough so far to deal with this. When you make a post using wordpress you will get the post on your home if you set it to be displayed on the homepage of course, then you can find the exact replica of the post in the particular category page, tag page and archive page as well. This brings in a serious in site duplicate content issue which sometimes search engines do not like at all. although inclusion on rel=canonical has brought down the problem to some extent, but still its not out of threat. So how to deal with this issue on wordpress?
Setting Your Tags, Category and Archive Pages To Display Excerpts
Except for the home page where some people prefer to display the entire content of their recent post and post page where you have no option other than to display the entire post, other parts of the blogs such as tags, archive, author and category pages can be made to display the excerpts all you have to do change this is by looking in to the specific template file and change the code
That’s how easy wordpress has made things for us.
Using noindex and nofollow tags
Before we proceed any further I want to clear your heads a bit about nofollow tag, many people think that nofollow links are of no use and search bots do not look in to it. This is a wrong assumption, search engines do crawl through nofollow links as well and index pages, but adding nofollow tag is just to instruct the Google bot not add any pagerank value or authority to the links, thus making it less valuable in terms of SEO, noindex tag on the other hand prevents indexing of specific page or category or any part of the blog or entire blog as a whole making it more powerful.
In order to instruct search engines only to index the contents in your home page and exact post page and not the other replicas found elsewhere in the blog use the following code in your header.php
This code instructs the googlebot and msn bot to follow links present in the homepage and exact post page but do not index them if the contents are not in blog index or post page. You can replace the follow tag to nofollow if you do not want the links to be followed which is a personal preference.
Also there are people who like to have their tags and archive pages to be indexed as well for some specific reasons. Its totally up to you whether you want contents on the other pages not to be indexed or to be.