Character Rules for Google and the Dash

Google's search results can influence Web-domain and website success.

Formulating domain names requires careful consideration of the way you construct your Uniform Resource Locator, or URL. Once you register your domain name and begin building your website, you must consider the way you name your pages and sub-domains. Constructing search queries on Google involves planning your criteria to evoke the most useful results. The dash character can play an important role.

Character Use on the Web

If you've ever downloaded a file from a website and tried to find it on your hard drive, only to lose track of it completely, you may be surprised by the name under which you eventually discover it. Its creator might have named it "my file.pdf," but on your system, you'll find it as "my%20file.pdf." That's because like other characters you type every day, the space may not be understood in the same way by all operating systems and languages. In online use, these unsafe characters must be replaced by specially encoded entities. By contrast, the dash and the underscore appear within the basic set of safe alphanumeric and special characters allowed in a URL.

Dashes

You'll find many domain names that include dashes, either because the unpunctuated equivalent wasn't available when the site owner secured the domain, or because she believed that the use of dashes made individual words within her domain name easier to read and recognize. You'll also see dashes separating individual words within the names of Web pages. Thus "my Web page" becomes "my-Web-page" in the location line of your Web browser, the area in which you type or paste the address of the page you want your browser to display. This occurs frequently on sites built around a content management system such as WordPress, in which page names equal page titles.

Underscores

Underscores serves as the dominant alternative to dashes in Web usage, particularly in the names of Web pages. Some Web professionals dislike underscores because they become difficult to see in a browser's location line. Others deprecate them because of their impact on Google search optimization and results. Parsing out exactly how Google translates underscores, and how it uses them, requires some detective work, but the results show why dashes prevail and underscores take a back seat.

Search Terms

Google treats two terms separated by a dash as separate words. Conversely, it regards the same two terms as a single word if you substitute an underscore for the dash as the separator in their midst. These results pose significant consequences for a website's ability to achieve good placement in search results. If a Web searcher looks for "my_page," the results returned echo back the search phrase and don't find the words within it. The same search for "my-page" yields both words, not just the combination of the two. Even though Google considers dash- or hyphen-separated terms to hold a strong connection to one another, it's capable of regarding them as separate words, whereas underscores don't constitute word boundaries.

References

• Google: Inside Search: Operators and More Search Help
• Phil Ringnalda, a Digital Magpie: Underscores Are Bad, Mmkay?
• Syncrony World Class Web Solutions: The Dash Is the Way to Go for Web Page Names
• SEO Blog @ TheSeoWorld: Should I Use Dashes or Underscores to Separate Keywords in URLs?
• Search Engines News: Google Test: Hyphen and Underscore
• Matt Cutts: Gadgets, Google, and SEO: Dashes Vs. Underscores
• Index DOT HTML: URL Encoding

Resources

• Google: The Evolution of Google Search