If you want to track who has a CD or other album you have out on loan, you could enter such a loan in the Notes field like so:
loanout  put person, date and any comment here (don't forget the space after  "loanout")

When it's returned you could add this line:
loanin  date returned goes here

Then if you wanted to see which albums haven't been returned yet you could go to the Report Writer and enter for Albums Filter Expression:
  contains(notes,"loanout") and not contains(notes,"loanin")

If the same album was returned and loaned out again you would enter the new loan info in the loanout line and delete the loanin line at that point.

Of course, you could call loanout and loanin something else so long as you are consistant.