Often pages or sections of your site have developed some link love that would better serve other pages you would prefer to have ranking or you would rather have users spending time with. So what you need to do is get those bank links and PageRank where you need it.
Redirects and Search Engines
Redirects automatically send a visitor to a specific page once the visitor accesses the site. The redirect can be to another page on the site or to a completely different site altogether. Redirects come in a few flavors the most important for this discussion are 301 redirects which are viewed as permanent and 302 redirects, seen by spiders as temporary.
Redirects, regardless of type, have been identified by SEO professionals as PR killers. Matt Cutts, a Google Software Engineer, stated in a Search Engine Strategies conference that "...clear disclosure to machines won't pass Page Rank [with] a 302 redirect." Even today there are hackers and crackers using redirects to hi-jack websites, even though spiders are capable of detecting nefarious activity. The behavior of 301 redirects however is quite the opposite.
However, on-site redirects are commonly employed by site owners to increase site visibility on SERPs and to take the visitor to the "good stuff." Here's how this technique is employed:
On-Site Redirects: the Basics
It's important to recognize that the structure of your website is pivotal to long term success in search engine result pages.
The site owner or SEO optimizes a deep site page to the max. The only point of this page is to rank highly on SERPs and in some cases, the text on the SERPs link is unusable by humans because it's designed for SEO only. Botspeak. However, once the visitor clicks the SERPs link to the highly-optimized page, he's automatically redirected to a page or a site designed for human use, i.e. optimized for conversion.
Note: Search engine algorithms can easily detect redirects and, frankly, they are still viewed with suspicion by spiders. In fact, a site page may be penalized. The entire site may be whacked if the redirect is deemed suspect.
Spiders are not opposed to redirects per se. In fact, if the redirect is considered valid - as in the case of a blog that delivers a "confirmation of receipt" page before redirecting the visitor to the blog post itself. This is viewed as an acceptable practice because it provides benefit to the search engine user.
Using Redirects Wisely
A link is a redirect - taking visitors to other pages of a site. Embed text links on high ranking pages deep in the site. Optimize these pages for SEO and employ redirects to take visitors to the appropriate zone or page of the site. Example: A site selling insurance products employs the following on a page deep in the site:
"Unfortunately, you never know what the future holds, but you can protect your loved ones now and in the future."
The link is embedded in informational content, which ranks higher, deep within the site. By placing the text link within this informational context, the visitor is provided an immediate option to the now-recognized risk - the lack of term life coverage.
Internal linking is a critical consideration in site design and content architecture. Creating highly optimized pages designed to appeal to SEO bots deep within a site (the site archives, e.g.), with links to pages higher up in page hierarchy is a legit use of what in effect is a redirect, though bots won't see these links as such.
Robot.txt and NoFollow
The redirect will be instantaneous (almost) to visitors, adding maybe a second to download times. However, bots will righteously crawl these sites whenever the opportunity arises - and that includes anytime a visitor with a Google toolbar installed visits your site. Googlebots are aggressive little letter-string junkies. A visitor can initiate a crawl so you want to be prepared for on-site bot activity.
Clearly identify those pages that are not to be indexed. This can be by individual page with nofollow or noindex tags, or if there are a number of pages designated off limits to spiders, create a robot.txt file.
A robot.txt file is developed identifying all pages off limits to spiders and placed in the site's root directory. Remember to update the site's robot.txt file as more pages are added to the site.
The objective of redirects is on-page optimization - both SEO and conversion ratio optimization. At this stage in the purchase sequence, the prospect has demonstrated enough interest to click on a deep link to learn more about products and services. Once that link is clicked by a human or tracked by a spider, both bots and eyeballs must be happy with what they see.
A key point for non-tech site owners: bots wouldn't know an attractive site if it bit its digital butt. Bots never see the presentation layer, which could be a mess. Bots read the black and white HTML and XML data that forms the site's structure. On-page optimization will appear in the page's code.
On-page optimization involves the deployment of links - which information links to what zone or page? Each page is optimized to drive the visitor deeper into the site and to, ultimately, convert.
Placement of "trip-wire" links is an essential aspect of page design. Trip wire links are embedded in content that evokes an emotional response in the reader, a response that demands immediate action. The example of the embedded insurance link above is a good example of trip wire links that optimize each page for conversion and for more expansive and complete indexing of the site by bots.
Remember, bots follow links. Embed links deep in your site on highly ranked pages. These links automatically redirect the visitor to less optimized but more human-friendly pages or sites.
Embed text links deep in site text with text embedded, intra-site links placed for maximum emotional response, i.e. a link to a sign up page embedded in an informational article about the benefits of jogging. Spiders and humans will follow well-placed, contextual links embedded in the body text.
This insures that spiders stay on site longer, indexing more pages and more accurately placing indexed pages within the right folder of the search engine's classification system (the taxonomy employed by Google, Yahoo, etc. determines how and where a site is classified).
Further, redirects can increase both page rank and site revenues when on-page optimization and nofollow and robot.txt files are used to direct the activities of bots. Remember, a Googlebot will try to crawl any site visited by a user with a Google toolbar installed so, virtually any visitor is a potential opportunity for Googlebot to spider a site.
Employ redirects to appeal to both spiders and humans and redirect a site's page rank in the process.