Abstract: A file sharing system may comprise a server configured to store a sharing file having one or more versions and an identifier of the sharing file, receive the sharing file and the identifier of the sharing file from one or more devices, and determine a version of the received sharing file corresponding to the identifier of the sharing file by using a hash value of the sharing file and a time editing the sharing file. A file sharing method may comprise sending, by a server, one or more messages associated with a sharing file to one or more devices which store the sharing file and have authorization to access the messages associated with the sharing file.