Short answers, pulled from the story.
Direct ascent is a proposed method of landing a spacecraft on the Moon directly, without assembling the vehicle in Earth orbit or carrying a separate landing craft into lunar orbit. Under this approach, a single large rocket would carry the crew and an attached landing module from Earth to the lunar surface in one flight.
NASA rejected direct ascent because it would have required developing a prohibitively large launch vehicle, either the Saturn C-8 or the Nova rocket. The agency chose Lunar Orbit Rendezvous instead, which needed only the smaller Saturn C-4 or C-5.
Direct ascent for Apollo would have required either the Saturn C-8 or the Nova rocket. Both were considered too large and costly to develop, which led NASA to pursue alternative mission architectures.
The Soviet engineering firm OKB-52 developed the UR-700 modular booster to carry the LK-700 spacecraft on a direct ascent lunar mission. The Soviets ultimately adopted an approach closer to NASA's Lunar Orbit Rendezvous model for their main lunar program, using a Soyuz spacecraft and a one-man LK lander.
The Soviet N1 rocket launched four times: on the 21st of February 1969, the 3rd of July 1969, and again in 1972 and 1974. All four attempts failed.
Rocketship X-M and Destination Moon both depicted direct ascent missions in science fiction film. The comics album Explorers on the Moon also portrayed a direct ascent mission to the Moon.