Center of gravity: intersection point of midline. Assuming the center of gravity is O, for midline AD, there is AO = 2OD.

Inner heart: the intersection of the bisector of the angle is equidistant from the three sides and is the center of the inscribed circle.

Outer center: The distance from the intersection of the edge perpendicular bisector to the three vertices is the same, and these three vertices are the centers of the circumscribed circle.

Vertical center: the intersection of high points, with no special properties.

Center: only used for equilateral triangles, and the center is the coincidence point of all the above centers.