Introduce of the name National Music Arts hall, GUKAK.
GUK means Country, Nation and/or National.
AK means Music.

Over those two letter was quoted from Chines characters.
History of Korea is roughly 5,ooo years, and Korea and Korean have adopted Chinese characters and use to use last 2,000 years.
Nowadays, 20C, 21Century, we are using completely, totally our own character, HAN-GEUL.

And One of Korean Dynasties throughout 5,000 years, 
JOSEON Dynasty, which was established 1392 to 1910.
One of King of Joseon Dynasty,
“King SEJONG the Great” had created in 1446 our own and completely and totally creative character in the World.
HAN-GEUL was consist of 28 alphabets beginning of creation in 1446 A.D, but nowadays we are using 24 alphabets,
10 vowels and 14  consonants, then we are able to express all kinds of human being’s sounds, animal sounds, even sounds from natures like winds and most of sounds in the World.

Sometimes we are still using Chinese characters.
Chinese character is a kind of logogram letters like Egyption letters, and Korean alphabet is a kind of Phonogram or Phonetic script/writing letters like English alpabet letters.