In ancient Korea, people used many different kinds of swords with different length and blade types. One type of sword could be used any time depending on the situation, but they had their own use.
The sword used for Ssangsoo Gumbup was the one which had only one blade with the name 'Do' at the end of the sword name. The sword which had two blades on both sides had the name 'Gum' at the end of its name. This type of sword was almost the same as Chinese sword.
In Haedong Gumdo, however, normally we just call them a 'sword' without distinction and use both words - 'Do' or 'Gum'.

Ssangsoo Gumbup
Ssangsoo Gumbup mostly uses both hands for strikes (swings or cutting, Begi) and blocking (defense, Mak gi). The word 'Ssangsoo' means both hands.

Ancient Korean warriors practiced this sword techniques (Ssangsoo Gumbup) for battlefield use. Even though this style can be used for one-versus-one sword fighting, its main goal focused on one-versus-many battlefield combat.
The sword used for this style was heavier and longer than other swords in order to give a strong and fatal cut effect to the opponents in armor and helmet. The length of the sword was from 120cm up to 2m and its weight was about 2 kg.

Nevertheless, in Haedong Gumdo, we do not use that long sword as today's Gumdo practice is for self-development of body, mind and spirit, not for battlefield combat. Thus, the sword used for Gumdo practice is 1m long.

Shimsang Gumbup
Shimsang Gumbup is splendid but fierce and vigorous. It is the core version of all Ssangsoo numbers. Shimsang Gumbup is also focused on self-discipline and harmony of mind and body, free from the sense of fear and the limits of life and death.

On the other hand, one of the key points is Shimsang Gumbup is using psychological status of the oponents. Showing unguarded points and laying the body open to the opponents' attack, you temp the opponents to attack you first. But you are securily guarded and can attack at the very second you catch the opponents ungarded points. Once the attack is started, the opponents do not have time to block it because the attack is consecutive and strong, consisted of multiple strikes that the opponents can not expect.

Yet, today's Shimsang Gumbup is focused on self-practice to make the person in accord with the sword.

Yedo Gumbup
The original meaning of the word 'Yedo' is the name of a type of sword. In brief, the meaning is 'sharp' and 'short'.
Therefore, the length of Yedo was shorter than the one used for Ssangsoo Gumbup and lighter. This sword was usded in normal times rather than in fieldcombats. Yedo Gumbup was mainly used by warriors of Gogooryeo - the strongest empire in Korean history.

Yedo Gumbup has four technical bases - sight, hitting, stance and cut. All four elements are very important as the used sword is short, light and sharp. It needs a smart grasp of the situation, accurate and fast hitting and cutiing, shrewd and prompt action of body, and prompt use of steps.

Baek Doo Gumbup (Jang baek Gumbup)
Baek doo is the name of the highest mountain in Korean peninsula and was the heart of Gogooryeo Dynasty in ancient times. As mentioned above, Gogooryeo was the strongest dynasty in Korean history which had almost equal power to ancient China and huge terrirory. The north-eastern part of China, such as Heilongjiang, Jilin, Liaoning, and part of Inner Mongolia and Hebei belonged to this empire.
Jang baek is Chinese name of Mount Baek Doo.
Baek Doo Gumbup was the sword art that had been used by the warriors of Gogooryeo.

Bon Gook Gumbup
This style had been practiced by soldiers of Geum wee yeong - the King's Royal guard that was in charge of King's safety and the defense of capital city - of Josun Dynasty after several Japanese invasions to Korean peninsula in 16th century.
Therefore, Bongook Gumbup was originally designed to defeat Japanese sword techniques after a long-time of researches and studies of Japanese sword fighting style.

Haedong Gumshik
This is the last version of all two-handed styles. All the highest techniques of two-handed sword arts are integrated into this style.