These new channels are meant to complement YouTube's core user-generated amateur videos and the non-exclusive, professional movies and TV shows it redistributes.

The strategy is intended to attract more viewers to YouTube, already the web's most popular video site, and offer advertisers new opportunities for marketing their products.

The new channels will also make YouTube a more direct competitor to producers and broadcasters of original, professionally-produced programs, including other Internet companies like Yahoo, as well as TV and cable networks.

YouTube has been setting the stage for the rollout of these channels over the past year or so through programs that offer funds and training to video content creators.

"These channels will have something for everyone, whether you're a mom, a comedy fan, a sports nut, a music lover or a pop-culture maven," wrote Robert Kyncl, YouTube's Global Head of Content Partnerships, on Friday.