Latches make up the oldest group of traditional black door ironmongery and are typically operated by pressing the lever with a thumb, hence the term thumb latch. Early thumb latches were made from wood and string, then wrought until they became virtually obsolete in they 1800's with the invention of the rim lock. The latch mechanism was reintroduced at the 1876 Worlds Fair. Cast in decorative brass and bronze and paired with back plate and lock, the latch is a familiar welcome for many home owners. Today, the latch is popular for entryway door sets, although the mechanism is far more sophisticated than earlier designs.
An important point to note is that the traditional thumb latch is designed for gaining access from both sides of a door. For a cupboard, it is recommended that you use a latch set, which is in effect the reverse side of a Suffolk Latch. Another variant of the thumb latch is the Cottage Latch. Instead of using the thumb, a ring is turned to release the mechanism and allow entry.