 In 1970, Western Union in co-operation with the Postal Service introduced the "Mailgram", a special type of telegram offered by Western Union intended for bulk mailing to multiple addressees.The sender would contact WU and submit to them the message to be sent and a list of addressees to mail the requested Mailgrams to.The message and address data were then sent electronically over Western Union's terrestrial network normally used for standard telegrams, with WU's Westar 1 satellite used instead starting in 1974 with its launch, for Mailgram transmission to participating Postal Service centers, who would then print and mail the Mailgrams to the requested addressees.