This IDC study outlines IDC's IT market taxonomy for IDC's Worldwide Black Book, 2005. It includes detailed methodologies for each of the major market segments included in the Black Book, along with detailed category definitions. It provides a summary of Black Book methodology, in which capacity it is intended for use as a handbook for the Black Book. It also provides discussion of measurement issues relating to translation of foreign currency exchange rates, market aggregation, and modeling measurements.

"The Black Book taxonomy is reviewed annually by a committee of worldwide and regional analysts to determine updates based on current research segmentation and methodology across all international regions. As such, the taxonomy evolves in line with IDC research practices and with the evolution of the industry as new technology sectors are added to the taxonomy over time." Stephen Minton, vice president, Worldwide IT Markets