Surface mail

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.
History.
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.
By country.
Israel.
The Israel Postal Company () offers international surface mail (known as "sea and land mail," ().
United States.
<section begin=USA />In 2007, the US Postal Service discontinued its outbound international surface mail ("sea mail") service, mainly because of increased costs. Returned undeliverable surface parcels had become an expensive problem for the USPS, since it was often required to take such parcels back.
Domestic surface mail (now "Retail Ground" or "Commercial Parcel Select") remains available.
Alternatives to international surface mail include:
Senders can access the International Surface Air Lift and ePacket services through postal wholesalers. Some examples of such wholesalers include:
If a sender sends an ISAL mailing directly through the USPS (without a wholesaler as an intermediary), the minimum weight is 50 pounds per mailing.<section end=USA/> ePacket mailings can never be sent directly through the USPS; senders must always use a wholesaler.