Reston

Facebook remains the number-one social-networking site in the world, according to a new study released Tuesday by comScore -- and it has undergone 153 percent growth in the past year.

The Reston, Va.-based research firm said most of the growth for social-networking sites is outside North America. On this continent, the social-networking audience grew nine percent, but the growth was much higher elsewhere -- 66 percent in the Middle East-Africa region, 35 percent in Europe, and 33 percent in Latin America. Social-networking sites for the world at large grew about 25 percent.