Registering a domain name for a long period of time may help websites improve search engine rankings, a new study claims.

Research by Webmaster World suggests those who register a domain name under Google for a period of ten years are less likely to be reported as spam, and so will get higher rankings, reports E-Consultancy.

The US Patent and Trade Office told the publication: "Valuable (legitimate) domains are often paid for several years in advance, while doorway (illegitimate) domains rarely are used for more than a year."

E-Consultancy added that long-term registration also helps users take advantage of the traffic their websites build up.

However, it claimed Britain's .co.uk domain name could only be registered for a maximum of two years.

Earlier this week, Google was claimed to be America's most popular search engine.

Figures released by Nielsen//NetRatings showed that in October the website was used 3.1 billion times.