Telex

Telex was a switched network of teleprinters — typewriters that talked to each other over phone-style connections. Launched in Germany in 1933 and spreading worldwide, it let a business in one country type a message that printed instantly on a machine in another, each subscriber reachable by a telex number. Because messages carried an answerback code confirming the receiving machine, telex became the legally trusted channel for banks, shipping firms, and newsrooms. It was slow and used a stripped-down character set, but it was reliable. Fax, then email, offered the same reach with images and full text, and national telex networks shut down through the 1990s and 2000s.