If you're born in the late 40's, you'd probably have been exposed to some punch cards but when starting work, it'd be the 70's already. I'm sure there was still punch cards around at the time, but at least you had printing terminals if not monitor-based terminals.
That said, depending on where you were working, things could also change fast. You could find yourself finding that a kernel system call had changed because someone patched it the evening before.
