The final choice of lunar orbit rendezvous changed the CSM's role to the translunar ferry used to transport the crew, along with a new spacecraft, the Lunar Excursion Module (LEM, later shortened to LM (Lunar Module) but still pronounced ) which would take two individuals to the lunar surface and return them to the CSM.
The final decision regarding lunar orbit rendezvous altered the CSM's function to a translunar ferry, transporting both crew members and a new spacecraft, the Lunar Excursion Module (LEM), which would take two individuals to the lunar surface and return them to the CSM.