Should you use an underscore or a dash in URLs? And why should you care?
This debate crops up time and time again within the SEO community. In attempt to clear the air, I looked into what Google has said on the subject and scanned up to 3,000 search results.
What Google says
This is Google’s most recent post on the subject on the Webmaster Central Blog:
"Webmasters asked about the difference between how Google interprets underscores and dashes in URLs. In general, we break words on punctuation, so if you use punctuation as separators, you're providing Google a useful signal for parsing your URLs. Currently, dashes in URLs are consistently treated as separators while underscores are not. Keep in mind our technology is constantly improving, so this distinction between underscores and dashes may decrease over time. Even without punctuation, there's a good chance we'll be able to figure out that bigleopard.html is about a "big leopard" and not a "bigle opard." While using separators is a good practice, it's likely unnecessary to place a high priority on changing your existing URLs just to convert underscores to dashes."
Source: http://googlewebmastercentral.blogspot.com/2008_01_01_archive.html
Date: January 22, 2008
This confirms what Matt Cutts wrote back in 2005:
"So if you have a url like word1_word2, Google will only return that page if the user searches for word1_word2 (which almost never happens). If you have a url like word1-word2, that page can be returned for the searches word1, word2, and even “word1 word2."
Source: http://www.mattcutts.com/blog/dashes-vs-underscores/
Date: August 25, 2005
3,000 results put to the test
I thought I'd check whether this still applies today. I googled allinurl:click here for websites with "click" and "here" in the URL, and scanned the first 3,000 results on Google.com, Google UK and Google Australia for supporting evidence. The search returned a number of variations, with + (plus sign), - (dashes) and other variations on "click here".
However, a search on allinurl:click_here returned only websites with "click_here" in the URL. This confirms that underscores still aren't treated as word separators in URLs, whereas dashes and other punctuation marks are.
Whenever possible, use dashes over underscores. Using underscores as word separators in URLs and file names could still prevent your pages from showing on relevant searches. If your URLs already use underscores, Google advises against renaming your files just for that.
A 301 redirect is a powerful way to tell search engines that a page on your site, or your entire domain, has permanently moved to a new address. A 301 will redirect users to the correct page, avoid dreaded 404 errors and help preserve your search engine rankings.
The common thread across these examples is that the page move is permanent. For temporary changes, you should use a 302 redirect instead.
Benefits of a 301 redirect
A 301 redirect tells users and search engines that a page has moved permanently. It takes users seamlessly to the correct page and avoids those dreaded 404 error pages. This helps avoid lost traffic and sales from broken links.
A 301 redirect also has powerful SEO benefits:
Indexation
A 301 redirect helps search engines discover and index new content. If your existing site is established and crawled on a regular basis, a 301 redirect could get your new page indexed faster.
PageRank flow
A 301 redirect does pass PageRank from the old page to the new. However, Matt Cutts did reveal in an interview with Eric Enge that a 301 redirect does trigger some form of PageRank decay.
Matt Cutts: "I can certainly see how there could be some loss of PageRank. I am not 100 percent sure whether the crawling and indexing team has implemented that sort of natural PageRank decay, so I will have to go and check on that specific case. (Note: in a follow on email, Matt confirmed that this is in fact the case. There is some loss of PR through a 301)."
Anchor text flow
A 301 redirect will also preserve your backlinks’ anchor text, helping your new page rank for relevant searches. This is what Matt Cutts had to say about this in one of his Webmaster Central video posts in March 2009: "Typically, anchor text does flow through a 301 redirect, but we don’t always promise that that will always happen". You've been warned! Play the full video below:
Duplicate content
A 301 redirect can overcome duplicate content issues if you point pages with look-a-like content to the correct resource. For example, if your homepage is accessible from http://example.com and http://www.example.com, you should create a 301 redirect from one page to the other. Search engines may otherwise think they are dealing with 2 different pages each with duplicate content, and would not consolidate PageRank and anchor text across both. The end result is lower search engine rankings for what should be the most important page on your site.
Search engines will ignore your redirect if you pages are disallowed in the robots.txt file. Check that none of the pages you want to redirect are disallowed in robots.txt.
How long to keep a 301 redirect
You should keep a 301 redirect in place as long as people as still linking to your old content. Ending the redirect or taking your old content offline altogether will break that important connection between old and new pages. In turn, this could return your old pages to the search engines, trigger duplicate content issues and 404 errors.
However, you should really contact all webmasters linking to your old pages to ask that they update their links. While a 301 redirect does preserve anchor text and flow PageRank, it can only be a short to medium term solution given PageRank decay. If your old content has a large number of backlinks, focus on the ones you believe carry the most relevance and authority.
How a 301 redirect works
Before we look at ways to implement a 301 redirect, it is helpful to understand how they work. When servers deliver web pages, they send browsers HTTP responses. A typical HTTP response contains HTML code in the body of the message, and headers that only browsers can see.
Headers carry important information about the message – header fields include the status code (“200” if the page was found, “301” in the case of a permanent redirect or “404” if no page was found), the date the resource was last modified and more.
The following screenshot shows the server’s HTTP response in the case of a 301 redirect. The page I wanted to visit, http://example.com/old-page.html, now redirects to a new page on the same domain http://example.com/new-page.html. The header shows a "301" status code, confirms the page has been "Moved Permanently" and points the browser to the right page in the "Location" field.
How to implement a 301 redirect
How you implement a 301 redirect will depend on:
Your HTTP server (Apache or IIS)
Your permissions and access rights
Whether you need to implement domain redirect, or a page-specific redirect. If you are moving a web site from one domain to another, it is advised to be as granular as possible with your 301s.
If you are running Apache and have access to your server’s configuration files (such as httpd.conf), the following redirect directive would implement a 301 from an old to a new page. Check the Apache documentation for more information.
If you cannot change your server settings, you may still be able to implement a 301 redirect through .htaccess. An .htaccess file also contains server directives. It can be uploaded to your home directory, or any other directory for that matter. Check whether your web host allows .htaccess commands – it may have been disabled for security reasons.
If all else fails, you could still implement a redirect at the file level. Add a few lines of code within each of the files you want to redirect to generate 301 response headers. The following code snippets work with PHP, ASP and ASP.NET files:
301 redirect with PHP
Add the following code to output a raw HTTP header to the browser. Remember that header() must be called before any actual output is sent, either by normal HTML tags, blank lines in a file, or from PHP. It is a common error to read code with include(), require() or have spaces or empty lines before header() is called. Check the PHP documentation for more.
<?php
header("Location: /new.php",TRUE,301);
?>
301 redirect with ASP
You may already have used ASP’s Response.Redirect method. However, did you know that it sends a 302 status code instead of a 301? A 302 has none of the SEO benefits associated with a 301 because it marks a temporary rather than a permanent move. Use the following code instead to generate a 301 redirect in ASP:
If you've just setup a 301 redirect, it's always a good idea to check that all is working according to plan. These 301 redirect checkers allow you to do just that.
If you've just set up a 301 redirect, it's always a good idea to check all is working as expected. The following free online tools allow you to do just that:
Google Webmaster Tools: the "Fetch as Googlebot" application in Webmaster Tools will show browser response headers for any page you submit. The following should appear if your redirect is successful: "301 Moved Permanently"
HTTP Viewer: Rex Swain's HTTP Viewer shows exactly what an HTTP request returns to your browser - the status code, other header fields and the HTML body. It will test any URL you submit on your site or your competitor's.
RagePank.com: Scans different URLs for your homepage and returns the response code for each. A useful tool to flag potential duplicate content issues with your homepage.
Understanding a visitor’s goals and responding with tailored ads and landing pages could transform your PPC campaigns – through higher click-through rates, lower bids and higher conversion rates. This post discusses 3 different types of search queries and suggests ways in which you can build them into your campaigns.
Three types of searches
Search phrases typically fall into one or more of the following 3 categories:
Navigational searches are driven by users searching for a specific website.
Informational searches are driven by users looking for information online - this can take many different forms, from images to videos, news and reviews.
Transactional searches are goal driven. Goals can be commercial or non-commercial.
A research paper from B. Jansen et al. found that more than 80% of Web queries are informational in nature, with about 10% each being navigational and transactional.
Navigational searches
Navigational searches are driven by users looking for a specific website. They could be looking either for the homepage or a specific page on the root domain:
Top 10 search terms in the US
Source: Hitwise.com, Top 10 Overall Search Terms for the 4 weeks ending 06/12/2010.
Navigational queries remain hugely popular with users. In fact, the 10 largest search terms in the US are all navigational. Searches on "facebook" top the rankings, followed by "facebook login". Navigational queries also top searches abroad in the UK, Australia and Canada according to Hitwise.com.
Navigational queries are easy to identify when they contain portions of URLs or even complete URLs. Studies have shown than many searchers type in portions of URLs into search boxes as a short cut to typing the full URL in their browser's address bar.
Search marketing opportunity: should you be bidding on your own brand keywords? And what difference can it make if you already are appearing at the top of search results for searches on your brand name? The answer is that if you don't, your competitors could do it for you. Google AdWords allows advertisers to bid on their competitors' name in 192 regions, including the US and the UK. Rivals could bid on your name in an attempt to build awareness of their own brand and lure your customers away. Real estate on search results pages is extremely valuable. Maximise your presence with own-brand campaigns.
Informational searches
Informational searches capture a diverse set of queries, from checking directions to learning anything and everything about cup cakes or playing the latest Lady Gaga video. The common thread across these searches is that information is the ultimate goal behind the search.
Informational queries often fall in one or more of the following 6 categories:
General knowledge queries aim to learn anything and everything about a given subject. They may contain questions words (such as "what is"), comparison words (such as "difference", "or", "versus") and a diverse set of natural language terms.
Factual queries look for a specific answer to questions about the weather, time of day, currency conversions and more. Search engines have created custom tools to answer many of these questions directly from the SERP. See Google's Search Features.
Problem-solving queries seek advice, tips or instructions. Look for question words (such as "how to") and help words (such as "tips", "advice" and "tutorial").
List queries seek a collection of links or directories rather than a specific answer. Search terms in the plural form often fall in this category.
Resource-led queries can be focused on the media type ("images", "videos"), the file format ("pdf", "doc") or the content type ("lyrics", "recipes", "reviews" etc).
Local queries always feature the name of a place, city or country.
Search marketing opportunity: informational searches provide brands with opportunities to connect with people at different stages of the buying cycle. They are incredibly broad and diverse, accounting for more than 80% of search queries. If you worked within AT&T's online marketing team and realised that searches around broadband speeds were popular, you could create PPC campaigns and SEO content around "ways to boost broadband speeds", "broadband speed tests" and more. Providing users with value added content and tools is a fantastic way to keep your brand front-of-mind at every step of the buying cycle. Identify popular keywords in your industry and ask yourself how you can add genuine value. As not every search is a selling opportunity, prioritise the keywords you feel have the most commercial value.
Transactional searches
Transactional searches are goal driven. The purposes of these searches is to reach a web site where interaction will happen, whether paid or unpaid. Transactional searches can include buying goods and services online, registering with a new service, online gaming, illegal file sharing and more.
Search marketing opportunity: transactional keywords convert well for brands. This is because users tend to be in the very final stages of the buying cycle. In other words, they have already acknowledged their needs, assessed opportunities and are about to convert. If you worked within AT&T's online marketing team, you could reach out to customers in the final stages of the buying cycle with PPC campaigns targeting phrases such as "switch to at&t", "at&t special offers" and more. However, I know from experience that transactional search volumes are small in comparison with navigational and informational searches. This is why brands need to engage with users earlier in the buying cycle to keep their name front-of-mind.
Keywords are clues to search intent
When brain-storming keyword ideas for your PPC campaigns, ask yourself where they would fit across navigational, informational and transactional searches. Choose your ad text and design landing pages accordingly - users in the final stages of the buying cycle will respond best to a page with clear calls to action. The keywords people use often give us clues about their motivations. Put their "search intent" at the core of your marketing campaigns.
Few brands have embraced the Facebook Platform in the way Levi's has. Levi's introduces social shopping with Facebook Connect and new social plugins.
The Levi's online store embeds Facebook's new social plugins - the Like button on shopping pages and product pages - and much more. Clicking the Like button will publish your action to your News Feed and that of your friends. It will also connect you to the Levi's Page on Facebook. An easy way for brands to create a lasting connection with their customers.
However, Levi's went one step further, using Facebook Connect to create a Friends Store: a page on Levis.com that only shows the products your friends liked. A powerful way for brands to tap into recommendations and word of mouth in ways that weren't possible "offline". My "Friends Store" was empty as none of my friends have yet added the Levi's application to their profile - however, it could only be a matter of time before they do.
On any Google search results page, your ad competes for attention against up to 10 rival ads, 10 organic results and Universal Search feeds. Although writing great ad text is more art than science, you will find common themes across top performing ads. Here’s my take on the 4Cs of ad copy:
Clear
Be specific about the products or services that you’re promoting. Targeted ad text helps users understand whether or not your ad is right for them. In turn, this helps avoid poorly qualified clicks, keeping your costs lower and conversion rates higher.
Compelling
First capture attention with a strong headline. Using popular keywords in your ad’s headline tends to increase click-through rates. Keeping your ad copy consistent with the top keywords in your ad group will also help your Quality Score.
Call-to-action
Next, use your ad copy to encourage clicks. Be clear about why people should care at all – answer the “What’s in it for me?” question with benefits and unique selling points. Then encourage users to click through to your landing page with a relevant call-to-action, such as "Buy Online", "Search Now" or "Get a Quote".
Concise
Keep your message short and sweet. Google ads can contain up to 25 characters for the title, 70 characters for the ad text and 35 characters for a display URL. However, fewer characters may fit if your ad text contains wide characters, such as capital letters or punctuation marks.
Most advertisers expect their ads to show every time users search on their keywords. However, this can be far from true. You could be missing out on a large number of impressions, clicks and conversions.
Impression share metrics
Three AdWords metrics make it easy to measure your share of impressions in your target market:
Impression Share: the percentage of impressions where your ads were displayed out of the total available impressions in your target market.
Lost Impression Share (Rank): the percentage of impressions that wasn't received by your ad due to low Ad Rank. At times, AdWords will prevent ads from showing altogether if it believes they provide a poor user experience. You can improve your Ad Rank either by increasing your bid or by improving your Quality Score.
Lost Impression Share (Budget): the percentage of impressions that wasn't received by your ad due to insufficient budget.
Impression share metrics are only available for campaigns opted into the Search Network. They are computed either at the campaign-level or the account-level. You can get impression share data through the Report Centre, when you run a Campaign Performance report, or an Account Performance report. You can also add impression share columns directly to the AdWords online interface.
Ways to improve your Impression Share
To increase your Impression Share, your ads need to appear more often within your target market.
Increase your CPC bid: a higher bid can lead to more ad impressions. When you raise your bid, you increase the likelihood of your ad appearing on the first page of results and receiving more impressions. This increase in impressions can occur even if your maximum CPC bid already is above your first page bid estimate. This is because AdWords considers dynamic factors, such as Quality Score, computed every time a search is run when deciding how to rank ads.
Improve your Quality Score: the Quality Score for ads shown on the Search Network depends on a number of criteria, the most important of which is Click-through rate (CTR). Experiment with different ad texts within each of your ad groups, before focussing impressions on the better performing ads to improve your Quality Score.
Increase your campaign budget, if you are losing impressions because of an insufficient budget
More ways to expand your coverage
Boosting your Ad Rank and increasing your campaign budget will help you capture a greater share of impressions within your target market. However, you could also look into ways to redefine and expand your target market:
Add more keywords, such as relevant singular and plural variations.
Remove negative keywords if you believe they may be too prescriptive.
Consider relaxing your keyword match type from Exact or Phrase to Broad.
Adjust other campaign settings, such as scheduling or location preferences.
Any of these changes could reduce your Impression Share, as your ads will have many more opportunities to show. However, they will also grow your campaign's reach.
A few words of caution
Not every advertiser’s goal is to appear every time his ads have the opportunity to show. The amount of money you can bid on certain keywords will ultimately depend on your CPA targets. Likewise, increasing your campaign budget may not always be an option. However, Impression Share is a useful way to diagnose your account and identify areas for improvement.
Whenever possible, use dashes over underscores. Using underscores as word separators in URLs and file names could still prevent your pages from showing on relevant searches. If your URLs already use underscores, Google advises against renaming your files just for that.
