7. An image forming method using an image forming apparatus, the method comprising the steps of: discriminating, by the language format discriminating section, a description language format of electronic data; and changing, by the image forming apparatus, a threshold value based on the discriminated description language format, there being a common storage area wherein a plurality of areas coexist in accordance with the threshold value, the plurality of areas being used to generate and store a plurality of pieces of data that have different formats based on the electronic data.
9. The image forming method of claim 7 , wherein in the changing step, a sheet size of each page is obtained from the electronic data in the description language format and the threshold value is changed in accordance with the maximum sheet size of the obtained sheet sizes in a case where it is determined that the description language format includes information that indicate sheet size of each page, based on the discriminated description language format.