LSMW is widely used by EDI programmers. EDI Programmers connect the SAP system to Non SAP system. During this Data migration is a necessity. When data migrates from source to destination the destination code is different from the source code. So what LSMW does is * Converts the data in to batch files * Then converts the batch files in to source code batch files * And then migrates data. Standard Interfaces like BAPI or Idoc are used in this process.