Roll a ball under your hand on a table and roll a pencil in the same manner. What you feel are "point" and "line" bearings. But to understand what mechanics mean by a surface "bearing," grasp a pencil in your hand and use your other hand to make it turn as a piece of shafting. Now, the lower half of the shaft is supported everywhere by contact with your hand - the upper half is not supported, merely covered. The advantages of ball and roller bearings were obvious many years ago to mechanical people... Solid steel rollers, being inflexible, were not satisfactory at that stage, but a Hyatt flexible roller bearing was different. We had something. Our spirally wound tube roller had a springlike quality, yielded to irregularities caused by poor manufacture, thus making automatic adjustments between housing and bearing.