The sliding doors are much popular in Japan in the old times and now, do you know the reason ?

It's mainly because that, the space is at a premium position in Japan,and a swing door need more space when it open. Also traditional housing was modular so that room size could be changed as needed. The partitions between rooms were little more than paper on a frame, the slide along wooden grooves could also be easily to remove if necessary. Therefore from old times the room dividers could slid to side easily,which is much more practical.

On the other hand, historically Japan is a very poor country in terms of natural resources and flat buildable land. While there is timber it was and is the dominant building material,there was not enough coal to go around, consequently, there not enough iron and steel for such luxuries as forks, spoons and hinges. Japanese architcture didn't develop because of a minimalist aesthete but because of a lack of raw materials and the feudal serfdom system in which a burgeoning middle class clamoring for larger houses didn't arise until the late 20th century.

Based on the key reasons above, the sliding doors are much more popular than swing doors in Japan .