What changed in south korea from 1961 to 1993?

Well for one, the time, the country was 32 years older.
Park Chung-Hee took power in 1961, and stayed in power until 1979.
Five Year plan in 1962, to try to growth national economy.
Second Five Year plan began in 1967, and targeted export-oriented growth as well as the steel industry.
Chun Doo-hwan took power in 1979 and stayed in power until 1988.

The constitution changed in 1986 to allow direct voting for the president. 

The person in power changed, as well as an economic growth, and a change in the constitution.
Hope this Helps!