Did you know?
The first letters sent over the Advanced Research Projects Agency Network (ARPANET) which is the prequel to the internet was ‘L’ and ‘O.’ Charles Kline (a student programmer) from UCLA sent the letters to Bill Duvall (another programmer) at Standford Research Institute at about 10:30pm on October 29, 1969. However, before Duvall received the letter ‘G’ from Kline his system crashed. Half an hour later the system was repaired to complete the message (login).
The programmers used the Interface Message Processor (IMP), built by BBN which basically allowed their computers to talk to each other. Today, the same IMP machine is at UCLA as well as the Log Book used to store all data about ARPANET. In addition, there is a plague and a coded message tile work in one of the building at the university commemorating the unprecedented event .
I have included a video above in which Leonard Klienrock (head programmer in 1969) of UCLA gives a tour of the IMP and explains programming. In the video in the middle of the post, Kline and Duvall speak of their experience.