[jarpadat]

OED gives the following usages, the first of which suggest users predate computers:

1950 Science 112 732/1 Analog machines..are enthusiastically supported by their users.

1959 E. M. McCormick Digital Computer Primer x. 139 The number of instructions which can be executed by a computer represents a compromise between the designer's and user's requirements.

[jazzyjackson]

Thanks for a good reference! It makes sense that "users of a service" or "user of a machine" slipped its way into computer jargon, no need to be coined or anything.

I'm tempted to pick up a copy of Digital Computer Primer on ebay, I love the old explanations of what these machines even are.