a recording medium readable by a computer , tangibly embodying a program of instructions executable by the computer to modify a document including a plurality of areas , a part or all of the plurality of areas including identification , is provided . the program includes the steps of inputting the document , inputting an instruction to the plurality of areas specified by the identification , modifying the document according to the instruction inputted to the plurality of areas specified by the identification , and outputting the document . according to the program , documents slightly different from each other can be created dynamically and easily , by use of a single original document and instructions , and thus productivity of the documents increases .