What are the characteristics of orthocenter?

Answer 1

Its at the point where the three perpendicular lines in a triangle drawn from each vertex intersect.

Answer 2

The orthocenter of a triangle is the point where the altitudes of the triangle intersect. It may lie inside, outside, or on the triangle depending on the type of triangle. In an acute triangle, the orthocenter lies inside the triangle; in a right triangle, it is at the vertex opposite the right angle; and in an obtuse triangle, it is outside the triangle.