For example: man(1), find(3), updatedb(2)?
man(1)
find(3)
updatedb(2)
What do the numbers in parentheses (Brit. "brackets") mean?
It's the section that the man page for the command is assigned to.
These are split as
Original descriptions of each section can be seen in the Unix Programmer's Manual (page ii).
In order to access a man page given as "foo(5)", run:
man 5 foo
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