An interactive computer program to display, process and analyze raw powder X-ray diffraction data is described. The program extensively employs graphic means of input and output with the help of “pop-up” windows and menus. In addition to those tasks that are common to most primary raw data analyzing programs, it performs many functions which are generally assigned to separate secondary programs. These functions include on-screen correction of d-spacing with reference to a standard compound, calculation of peak width and crystallite size, subtraction of patterns for differential X-ray diffraction and unrestricted overlay of patterns. The advantages of an integrated single program to process X-ray diffraction data in mineral research are illustrated and discussed.