Short answers, pulled from the story.
A planned economy is an economic system where investment, production, and the allocation of capital goods follow economy-wide economic plans rather than autonomous market decisions. In a market economy, firms independently decide production, distribution, pricing, and investment; in a planned economy, those decisions are coordinated through a central or distributed planning mechanism.
The Soviet government founded Gosplan in 1921, formalizing the planning apparatus. The period of the New Economic Policy intervened from roughly 1921 to 1928, and the first five-year plan began in 1928.
Project Cybersyn was a distributed decision support system launched in 1971 by Salvador Allende's socialist government in Chile. It linked firms to the government via telex machines and fed data into a computer-simulated economy with a real-time control room. In 1973, a CIA-backed military coup led by Augusto Pinochet overthrew the Allende government, abolished the program, and moved Chile toward a liberalized market economy.
Ludwig von Mises argued the economic calculation problem: without markets, planners lack prices and cannot rationally allocate inputs. Friedrich Hayek identified the local knowledge problem: individuals hold particular knowledge of their own needs and circumstances that no central authority can adequately gather or act on in time.
In the May 1949 issue of Monthly Review, in an essay titled Why Socialism?, Einstein wrote that a planned economy would adjust production to the needs of the community, distribute work among all those able to work, and guarantee a livelihood to every man, woman, and child.
No. Studies of Eastern Bloc command economies conducted in the 1950s and 1960s by both American and Eastern European economists found that those economies showed greater fluctuations in output than market economies during the same period, contrary to the expectations of both groups.