Hello Sharif,

the simplest explanation for a frame is local coordinate system. So the frame has a basepoint, a x-axis, a y-axis and a z-axis in Moi. Max has created a new combined datatype for points and frames called pointarray which has a high flexibility. Every element consists of 3 coordinates (x,y,z) and 3 Euler angles (Notation X,Y',Z'') and a seventh coordinate (maybe useful for homogenous proposes?). If you create a frame node, a pointarray with one element in it will be created. You can manipulate the angles to orientate this virtual frame. Typically nodes for objects, that needs a frame as an input in Moi, are labeled with center. Nevertheless you can also connect a point node to it, because the angle infos (point node has also pointarray output) and so the frame informations are present. Only limitation: The point node has no rotation inputs. The big advantage of Max design is the flexibility, reduction of wires and make uniformly arrays of points/frames possible. An good example for the flexibility is Max line node: You can connect a single frame or point as input or complete streams of points/frames -> pointarray. The node will do the rest!

I hope you get me, my english is not the best!
Karsten