True or False: A millisecond is a millionth of a second.

A millisecond is indeed not a millionth of a second; rather, it is one-thousandth (1/1000) of a second. To clarify, the metric prefix "milli-" denotes a factor of one thousandth, whereas one millionth of a second is referred to as a microsecond.

The confusion arises because both milliseconds and microseconds are commonly used in contexts involving precise timing, such as in electronics and programming, but they represent different orders of magnitude. This distinction is critical in fields like robotics, where timing and response intervals can significantly impact performance. Therefore, labeling the statement as false correctly identifies the misunderstanding about the metric prefixes used in measuring time.