Journal

Due to its multitasking nature, the Windows operating system was initially thought to be unsuitable for running time-critical experiments (Myors, 1998, 1999). This con-cern was caused by the fact that two or more programs running on a single-processor multitasking system are not truly running in parallel. At any given moment, only one program is running, while the other programs are preempted by the operating system. Thus, what is gen-erally called multitasking is achieved by switching back and forth at a fast rate between several running and pre-empted programs. For the human user, the rate at which this switching occurs is too fast to notice, giving rise to the illusion that the programs are running in parallel. For daily use, this type of multitasking is satisfactory, but for ex-perimenters interested in measuring reaction times, it is