I do many off the cuff things, because it saves me time. E.g. my boss
asked for a workbook to be cleaned up, and rows deleted based on a text
string being present.

A simple Do until loop, starting from the bottom, working upwards (since
we are deleting rows), and whole job was finished in ~15 minutes,
instead of ~10 minutes by using Autofilter (now that I think about it),
or 4 hours manually (estimated). SO, bad example, but the cookie
sometimes falls the other side of the tree, and VBA is the fastest way
to accomplish a task.

For your first and second question, you will have to refer to Wikipedia.
Search for "VBA". No history, though, but lots of links.

Things I do:

1- At work I manage resources in an Engineering test group; Engineers,
Test equipment temperature chambers, etc.

2- I also use it for charging other departments which use my equipment.

3- At home I ma using Exce/VBA for controlling my Ham radio equipment.
Reading / loading the memories in the radio. All via the serial port.