When you read about locks and lock mechanisms, several terms may be new and confusing. The term "lock hasp" can be especially confusing, because it may refer to more than one thing.
On a Padlock
The term "lock hasp" may refer to the metal loop protruding from a padlock. On a padlock, the U-shaped metal bar that releases when unlocked is sometimes called the hasp, but it is more commonly referred to as the shackle.
The term "lock hasp" may also refer to the style of latch most often used with a padlock. This latch uses a strip of metal on a hinge with a hole on the other end. Through this hole passes the staple, which looks similar to a link of metal chain. This staple passes through the hole, and it is secured with a padlock.
Roots and History
The word "hasp" has its origins in Old English and Old High German, and it refers to any sort of fastening latch. This style of latch has been used for centuries, and it may be plain or decorative in design.