Median of a Triangle Side
A median of a triangle is a line segment that connects a vertex to the midpoint of the opposite side.
Let's consider a triangle ABC.

The median of side CB is the segment that connects vertex A to the midpoint M on side CB, opposite vertex A.

The median of side AC is the segment that connects vertex B to the midpoint M on side AC, opposite vertex B.

Finally, the median of side AB is the segment that connects vertex C to the midpoint M on side AB, opposite vertex C.

Every triangle has three medians, one for each side.
The point where the three medians of a triangle intersect is called the centroid.

The centroid is one of the key points of a triangle.
And so on.
