Simultaneous interpretation was initially introduced and used at the Nuremberg Trials consisting of a set of military tribunals of the Allied Forces of World War II in 1945-46.
Then, in the late 40s and early 50s of the last century, United Nations officials launched simultaneous interpretation as the preferred method for most UN meetings, because it saved time and improved the quality of results.
In simultaneous interpreting, participants wear headphones and the interpreter translates the speaker's words into the target language as quickly as possible from the source language, while the speaker from the source language speaks uninterruptedly; the oral language interpreter, housed in a soundproof booth, speaks into a microphone while clearly seeing the speaker of the source language and/or listening through the headphones. Simultaneous interpretation is sent to the listeners' target language via their headphones.