Thanks very much.
I am trying this, but unable to get it to work so far. When I evaluate
Needs["myLibrary`"]
I get an error message:
Get::noopen: Cannot open myLibrary`.
Needs::nocont: Context myLibrary` was not created when Needs was evaluated.
I suspect there's a problem with how my search-paths are setup. All my notebooks, along with my newly created package, are in a directory, but I notice that directory doesn't appear in (dollar-sign, capital p, lowercase a, lowercase t, lowercase h) when I evaluate (dollar-sign, capital p, lowercase a, lowercase t, lowercase h). I have to spell out that variable, because Wolfram's website formats it strangely when I just try to type it in verbatim. So many surprises.
I'd rather not hardcode the full pathname into the Needs statement, because if my I did that, my code would break if I later moved my files to a different directory.
In C I would just do "include myLibray", and this common task would be very easy.