Version: 2018.2
public static Quaternion FromToRotation (Vector3 fromDirection, Vector3 toDirection);

Description

Creates a rotation which rotates from fromDirection to toDirection.

Usually you use this to rotate a transform so that one of its axes eg. the y-axis - follows a target direction toDirection in world space.

using UnityEngine;

public class Example : MonoBehaviour { void Start() { // Sets the rotation so that the transform's y-axis goes along the z-axis transform.rotation = Quaternion.FromToRotation(Vector3.up, transform.forward); } }