Etiquette: It is considered illegal to use the ARPAnet for anything which is not in direct support of Government business. At the Al lab, we use the network to talk to other researchers about all kinds of things. For example, personal messages to other ARPAnet subscribers (for example, to arrange a get-together or check and say a friendly hello) are generally not considered harmful. This is one of the ways in which we adapt the network environment to our community. It is very clear that without that sort of freedom, the network could not have evolved to its current point of technical and social sophistication. Sending electronic mail over the ARPAnet for commercial profit or political purposes is both anti- social and illegal. By sending such messages, you can offend many people, and it is possible to get MIT in serious trouble with the Government agencies which manage the ARPAnet.
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