Abstract: Personal Cloud Engine (iCloud) described in the present invention collects information relevant to a user from various data sources including personal email accounts, social network accounts, online vendors, on-line services for store and share photos and videos and on-line bank accounts. Collected data are classified, indexed, tagged and stored in a persistent data storage device. Web interface such as HTTP is provides for access data by a client, which can be web browser running on a computing device or a client application running on a smart phone. By gathering all the data, iCloud maintains a secondary copy of all valuable personal data and effectively prevents data loss. iCloud can also utilize the data and extract intrinsic value from the data stored by data mining and analytic tools.