Return statement or ReTurn from
Subroutine, a statement in many assembly languages and other
low-level computer languages
Request to send is the optional
mechanism used by the 802.11 wireless networking protocol to reduce
frame collisions introduced by the hidden terminal problem
Run-time system, a part of some
computer's runtime environment
Radio teleswitch service, which
regulates energy rates via broadcast radio in the UK
SIGRTMIN and SIGRTMAX or
Real-time signal, signals sent to computer programs for
user-defined purposes