The point of intersection of altitudes of a triangle is called orthocenter and point of intersection of the 3 medians of a triangle is called centroid
The three altitudes intersect in a single point, called the orthocenter of the triangle. The orthocenter lies inside the triangle if and only if the triangle is acute. The three vertices together with the orthocenter are said to form an orthocentric system.
The point where the lines interesect in a triangle is called the point of concurrency. Wen finding the altitude the point of concurrency is called orthocenter.