In several books and sites, it is written that torque is calculated about an axis, and angular momentum is calculated about a point. In MIT's Angular momentum lecture pdf, Angular momentum has been calculated about a point and then this has been used to calculate the torque about that point.
In this page, it has been explicitly mentioned that angular momentum is defined about a point in an inertial frame.
On some other websites, it was mentioned that torque is defined about a point and each point determines a unique axis in itself, about which the torque is the same for every point on that axis. Is this true? For central axes?
Which is true? Is torque calculated about a point or an axis? Is angular momentum calculated about a point or an axis? If torque and angular momentum are not defined in the same sense, then how can they be linked to Newton's equations (maybe due to the axial property of moment of inertia?)?