Internet Day

What the day is

Internet Day is observed on October 29. It marks the date in 1969 when the first message was transmitted over ARPANET, between a computer at UCLA and one at Stanford Research Institute.

The message was supposed to be the word login. The system crashed after two characters, so the first thing ever sent between networked computers was lo. They restarted and completed it about an hour later.

Origin and background

ARPANET was funded by the United States defense research agency, and the persistent story that it was designed to survive nuclear attack is only partly right. Survivable communications were a genuine motivation in the underlying research on packet switching; the network itself was built largely because computers were scarce and expensive, and researchers wanted to share them remotely.

Packet switching is the idea that mattered. Rather than opening a dedicated circuit between two points, as telephone networks did, data is broken into packets that find their own way across the network and are reassembled at the far end. That makes the network resilient and lets many conversations share the same links.

The internet as such arrived later, with TCP/IP, which allowed separate networks to interconnect. The switchover to it in 1983 is the moment a network became the network. The web came later still, in 1989, and is an application running on top rather than the thing itself, a distinction most people never need but which explains why email and the web are different animals.

Roughly a third of humanity still has no internet access, distributed very unevenly by income, geography and gender.

How to take part

• Look up how your own connection physically reaches you. The answer usually involves a surprising amount of fiber and at least one undersea cable.
• Check your router's firmware is current. It is the most neglected device in most homes.
• Turn on two-factor authentication somewhere you have been putting off.
• Read about the 1983 TCP/IP transition, which was a coordinated flag day across the whole network.
• Save something you value locally rather than trusting it to remain online.