11. A source electronic device comprising: a storage media to store a modular document, wherein the modular document comprises plural component documents; and a processor to: receive a request to send the modular document to a destination electronic device; in response to the request, determine which of the plural component documents is already available at the destination electronic device; and prepare a package to send to the destination electronic device, wherein the package includes the modular document and a subset of the plural component documents not already available at the destination electronic device, the modular document in the package including references to the plural component documents, and wherein the processor is to not include in the package one or more component documents determined to be already available at the destination electronic device.
16. The source electronic device of claim 11 , wherein each of the modular document and the plural component documents is identified by a corresponding unique identifier.