One of my earliest programming-related memories is of picking up a macro assembler manual for the SDS 940. This would have been in 1969 or 1970, when I was 11

One of my earliest programming-related memories is of picking up a macro assembler manual for the SDS 940. This would have been in 1969 or 1970, when I was 11 or 12, and my programming skills were limited to small BASIC programs. The assembler manual completely baffled me, but I recall to this day the first line of an example macro it contained: MUMBLE MACRO Of course this only deepened my confusion. Clearly there were profound mysteries here :-)