A prosthetic hand that weighs about half that of a human hand also enables wearers to carry out intricate tasks, such as tying knots ...

An curved arrow pointing right. Need to bust out a tie for an important meeting? You may remember some of the classic knots, but these 3 will keep you looking sharp at the office. Produced by ...

You can tie as many butterfly knots into a single line of rope as needed, which is especially handy with multiple climbers on a line of rope. But it's not just useful for climbing. The alpine ...