Starting with a Degree in Computing Science when 32k words (that would make it 128k bytes these days, but I seem to remember the manufacturer still had machines using 6 bits to a byte so it may well have been 96k in modern money!) was a boardroom decision which then had to be craned in to the 4th floor, after removing the external walls.
I retired from it all in 2003 after having been "IT Manager, Strategy and Planning" in a small part of one of the big banks before then moving on to a strange post where I had no staff, no budget, but had responsibility for the on-line banking service AND the call centres, but only when they failed . . .
My job at such a time of crisis was to know all the technology end-to-end and all the people who made the technology work and the processes they had to go through to make it all work. At the point when it failed, I became responsible for ensuring all this could be put back together again, using all the correct processes, but executed in minutes and hours, rather than the months and years it normally took to change things.
Put briefly, I knew everything but couldn't actually do anything!
Now, what do you want to know?