The historical development of books examination with utilizing science become inevitable to the machanization of library catalogues. With the advance of times, like this, a new- development of $Indention('||'&'||'$ : Kisun) must be sought for which is a kind of descriptive catalogues being used now. This paper is scheduled to grasp problems in the course of using and logical grounds of Indention which hal-e been used disordering. It must be considered that four kinds of Icdention settlement is suitable to the features of Korean letters. 1) TI-e must consider the features of Korean Language and Oriental Language writing(Japan, China). There must be a establishment of floating $Indention('||'&'||'E$ : Kisun), which are suitable for the writting style or hand writting man on the point of most of Koreans are depend upon hand witting, then books catalogues like western language, not left edge of the cards of the $Indention(B$ : Kisun) establishing, from edge to Call Number, from the last of the Call Number to First Indention(%-Bl63). First Indention(%-%%) to a space of Second $indention($\ulcorner^%)$ must be established and then, every catalogue and Indentions are distinguished surely. 2) \Then we consider the developing catalogue making in the future. It is important to establish a fixed $Indention('||'&'||'$ : Kisun) for machinization of typewriter(Korean, Mimeographing) and computer, etc ... not "Cm" unit but "Space" unit, and consider oriental letter, ne make more surplus space as a Indention, we can give anadaptablity of using machines. 3) Considering typography printing and type-setting printing by printing type, we must fit the $Indention(\ulcorner'||'&'||'$ : Kisun) as a "Cm" unit, and there must be a re-adjustment of $Indention(g$$ : Kisun) which considered the complexity of Call Number by a mass of collecting books like this, the establishment of Indention(E'||'&'||'j!: Kisun). We must not use a uilified one as a concrete conception by "Space" or "Cm" unit which has been used now but re-adjusted adaptably which can be fited as a method of making of catalogues. 4) The name of $Indcntion(J, S$ : Kisun) has becll called 7;arious methods until now, but English Indention which has been used without any concrete mexirig must be used as a ours fitable as a our mind. The above mentioned is presented as a Indention and examinational l~letilods by myself style, I wants these r i l l be helpful to the future developments of the machanization of Indention $(sf:$ Ki sun). Concrete studies must be continued in the future for development of $Indention(zj:$ : Kisun). : Kisun).