real time

real time  1. [techspeak] adj. Describes an application
   which requires a program to respond to stimuli within some small
   upper limit of response time (typically milli- or microseconds).
   Process control at a chemical plant is the classic example.  Such
   applications often require special operating systems (because
   everything else must take a back seat to response time) and
   speed-tuned hardware.  2. adv. In jargon, refers to doing something
   while people are watching or waiting.  "I asked her how to find
   the calling procedure's program counter on the stack and she came
   up with an algorithm in real time."