YouTube Tries Being Topical Directory

As YouTube continues to grow -- the site is now storing 35 hours of uploaded video every minute, up from 24 hours per minute in March -- Google's popular video site is exploring new ways to make its content accessible to users.

At a time when TV networks seek to restrict the availability of their content through devices like Google TV, YouTube is looking beyond keyword search to enhance the discoverability of its content.

On Wednesday, YouTube said that users can opt-in to an experimental service called "YouTube Topics on Search," an attempt to meld keyword queries with a topic-oriented directory.

"Put simply, we try to identify topics on YouTube and associate videos with them," explained YouTube software engineer Palash Nandy and UX designer Elizabeth Windram in a blog post. "We use many different sources to find these topics, including frequently used uploader keywords, common search queries, playlist names, and even sources outside of YouTube such as Wikipedia articles."

The way this is implemented is through the addition of query refinement buttons, labeled with a (+) sign, that accompany each video listed as a search result and through a menu bar labelled "Explore" that reveals a series of topic terms at the top of the search results page.

A search for "taekwondo," for example, produces a list of suggested topics to explore: kick, karate, martial arts, muay thai, human weapon, bruce lee, chinese martial arts, 540 kick, hyeong, and knockout.

By expanding the scope of keyword queries to terms and topics that are related, YouTube aims to encourage prolonged exploration and viewing, which should ultimately boost YouTube's ad revenue and strengthen the community aspect of the site.

YouTube's attempt to move beyond simple keyword searches reflects a broader effort by Google to provide more varied modes of information discovery, through services like Voice Search and Google Goggles.