A new search engine dubbed Cuil is hoping to offer a rival to the likes of Google, Yahoo and Ask.

Cuil is pronounced 'cool' and comes from an old Irish word meaning 'knowledge'.

The site has indexed 120 billion web pages, which it claims is three times more than any other search engine, and results are organised by ideas rather than just rankings. Cuil also boasts complete user privacy.

The new search engine will attempt to analyse the context of each page and the concepts behind each query, thereby grouping similar results together and sorting them by category.

These groups are divided by tabs which aim to clarify subjects, offer images to identify topics and search refining suggestions.

"The web continues to grow at a fantastic rate and other search engines are unable to keep up with it," said Tom Costello, chief executive and co-founder of Cuil.

"Cuil presents searchers with content-based results, not just popular ones, providing different and more insightful answers that illustrate the vastness and the variety of the web."

However, it seems that the new site has been more popular than its makers had anticipated, as the servers seem to have buckled under the strain.

Many users trying to access the site are seeing an error message which reads: "We'll be back soon ..."

"Due to overwhelming interest, our Cuil servers are running a bit hot right now. The search engine is momentarily unavailable as we add more capacity. Thanks for your patience," the notice says.