Radicals ( Radical16) two strokes in Kanji;

dimensional, e.g.

box (e.g. upside down box);

directional, e.g.

;

logical, e.g.

box (e.g. upside down box);
door;
IFF maki (i.e. female name);
waiting for 5W1H characters to the door (gate);

IFF Basic logic gate (e.g. AND, NO, OR, NAND, NOT, ... ), also see: Schematic Symbols;
IFF XOR logic gate, also see: Swap;

numerological, e.g.

2;

structural, e.g.

door alike surface to hold, and waiting for 5W1H characters to the door (gate) e.g. if sun character, light through a gate;

Radicals;