Google Panda & Penguin Introduction**UPDATED Oct 24th 2014**
You need to understand which algorithm, Penguin or Panda has penalized your website if you are going to fix it. Penguin is the cause if you can see a drop in Google traffic on the 24th April 2012.
There have been various penguin and panda launches during the past few years and if you have traffic data, you should be able to isolate a large drop in rankings to a specific time frame. Once you have a date for your traffic drop, take a look at this great post at http://moz.com/google-algorithm-change to determine which algorithm update hit your site.
In simple terms Panda affects your on-page stuff and Penguin affects your off-page (link based) stuff, so you should soon be able to determine whether your site has been hit for on site spam/low quality content, or because you have low grade, irrelevant links pointing at your site.
If it's Penguin/linking related, you should begin by analysing your current links.
Whichever keywords dominate your back-link anchor text will usually be the ones hit hardest by Penguin. There is a free back-link checking tool at www.majesticseo.com which will show you the search terms currently being used in your back-links.
Back-LinksThe Google Penguin algorithm requires text link density of less than 5%. A Google friendly linking profile will have mostly URL related links, Brand related links and lots of different ‘junk’ links instead of keyword rich links. Brand links are variations of either your website name or company name. URL links should be varied as follows to provide a natural link profile;
Getting links from different Class C IP addresses is really important (See here for how) for your back-linking strategy. It is more important than ever that your inbound links come from relevant, themed sites ( what are themed, relevant links? Find out here) rather than random content sites. The trust score of the domain carrying your link is important. A back-link from a page that is already being linked to from a quality themed resource is a great link to get.
Link NetworksWe would advise website owners to avoid automated link networks because they can't provide anything other than low grade links and when Google discover the network it will lose all its ranking influence and sites it links to will be penalized heavily. While it may seem like a good short cut, DON'T take it!
Google Panda RequirementsCheck your content is original, well written and that it adds value to 'the conversation'. If it does those three things then you are well on the way to building a useful website that your visitors will enjoy.
Check your meta-data tags in Google webmaster tools because duplicate tags on two or more pages can lead to a ranking penalty. Each page should have it’s own bespoke meta description data. The meta description tag is frequently used in search engine results below your page heading. For this reason you should compose it to get a better click through, not for keyword spamming.
How Visitors Engage with Your ContentGoogle penalizes slow loading sites. Check that your site is fast enough using YSlow in Firefox. The bounce rate for your website measures the amount of visitors that don’t like your content. This is an indication to Google that your content isn’t what visitors are looking for, and so you will see your website drop for the search terms with the highest bounce rates (More about bounce rate can be found here).
Page ViewsIncreasing the number of pages that your visitors look at is a good way of increasing the quality score for your website content. Getting your visitors to click through to a second or third page on your site is beneficial for your search engine rankings. The average time spent on your pages is an indicator of content quality. Website visitors should stay on your site reading your content for as long as possible.
If your site has a weakness in any of these areas then your search rankings will be affected. You need your site to reach a minimum standard for each element listed if you are going to rank well.
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