Pinterest has announced that the number of its monthly users soared by 50% in the past year to more than 150 million, with 80 million of them living outside the US. Co-founder and chief executive Ben Silbermann said the growth was particularly impressive given that Pinterest was not a social network. "Pinterest is more of a personal tool than a social one. People don't come to see what their friends are doing."People go to Pinterest for inspiration and ideas in the form of pictures and videos pinned to virtual bulletin boards showcasing various interests such as food, fashion and travel.With each new user, software at the service gets more data with which to personalise visual recommendations, according to the San Francisco-based company.Pinterest said it served up more than 10 billion recommendations daily, double the number delivered a year ago.Pinterest recently introduced video ads, and in June the company unveiled new features to facilitate shopping on the site, as the platform pushes to become an e-commerce hub.The offerings included a virtual shopping bag that users can fill as they cruise bulletin boards.Pinterest got involved with e-commerce last year with "pins" in mobile applications that let people buy items they see on bulletin boards.- AFP..