V-MAIL

V-mail was originally based on the British "Airgraph", and was an unusual and ingenious system for delivering mail from United States troops to home addresses during World War II. V-mail correspondence worked by photographing large amounts of censored mail reduced to thumb-nail size onto reels of microfilm, which weighed much less than the original would have. The film reels were shipped to the US, sent to prescribed destinations for developing at a receiving station near the recipient, and printed out on lightweight photo paper. These facsimiles of the letter-sheets were reproduced about one-quarter the original size and the miniature mail was delivered to the addressee.
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Eng: v-mail
Urdu: خفیہ ڈاک ۔ دوسری عالمگیر جنگ کے دوران میں امریکا سے باہِر امریکی افواج کو بھیجی جانے والی ڈاک جِسے پہلے خُود فِلم کی صُورت میں بنا لیا جاتا تھا ۔
  

n. корреспонденция на микропленке (посылаемая военнослужащим)

поща;

Special forms and envelopes used by U.S. forces during WW II.