Surface mail, also known as sea mail, is mail that is transported by land and sea (along the surface of the earth), rather than by air, as in airmail. Surface mail is significantly less expensive but slower than airmail, and thus is preferred for large or heavy, non-urgent items and is primarily used for sending packages, not letters.
The term "surface mail" arose as a retronym (retrospective term), following the development of airmail – a term was needed to describe traditional mail, for which purpose "surface mail" was coined. A more recent example of the same process is the term snail mail (to refer to physical mail, be it transported by surface or air), following the development of email.
On May 14, 2007, the United States Postal Service eliminated international surface mail as part of its cost-cutting measures. Domestic Ground Parcel Post (now "Retail Ground" or "Commercial Parcel Select") remains, as has been since 1913.
For items mailed internationally, alternatives include: