The lateral edges of a prism are actually the sides of the lateral faces, which join with the vertices of the base of the prism. In a right triangular prism, the length of the edges is equal to the height of the prism. It is important not to confuse them with the edges of the bases of the prism, which are the triangular sides (the two bases) of the prism. The lengths of the lateral edges will always be equal.
We use the lateral edges of the prism to calculate the area of the base, the volume, the area of the lateral surface, and the area of the total surface of the prism.