System and method for transferring data with electronic messages

A method for duplicating data associated with semantic data, comprising:

• receiving an electronic message that comprises at least one reference that uniquely specifies a set of data, wherein the set of data comprises one or more original data items that are associated with semantic data;
• presenting the electronic message to a recipient at a first computer system;
• in response to input to the first computer system, presenting at the first computer system some or all of the data comprised by the set of data;
• and
• in response to further input to the first computer system, creating a persistent copy of some or all of the data comprised by the set of data;
• wherein creating a persistent copy comprises creating a persistent copy of at least one of the one or more original data items that are associated with semantic data, such that each copy of a data item is associated with the same semantic data that the corresponding original data item is associated with.