Several users discuss resources for understanding instantaneous centres of rotation, with one recommending a specific website for foundational knowledge. A key formula is shared for calculating the speed of point B based on point A's speed and angular velocity. The condition for determining the centre of velocity is highlighted, emphasizing that it should equal zero. One user mentions using Kennedy's theorem to find instantaneous centres, noting that while it works, resolving velocities directly was quicker in their experience. The conversation emphasizes the balance between theoretical understanding and practical application in mechanics.