What tool is commonly used for opening mail?

A letter opener is designed specifically for the task of opening envelopes and mail efficiently and safely. It typically features a sharp blade or pointed edge that allows the user to slide it along the seam of an envelope, creating a clean opening without damaging the contents inside. This is particularly important in mail handling settings, where preserving the integrity of documents is crucial.

While options such as scissors, a stapler, and a knife could potentially be used to open mail, they are not optimized for this purpose. Scissors may tear the envelope and could be cumbersome for quick access, while a knife presents safety risks due to its sharpness and requires more care when handling. A stapler, on the other hand, is entirely unsuitable as it is designed for binding paper rather than cutting or opening. Thus, the letter opener stands out as the most appropriate tool for the job.