These two words can be confusing because they both refer to the end of a series.  But they are easy to distinguish.

• We use latest to refer to the most recent example of something.  There is no implication that there will be no more.

I really like Amy MacDonald’s latest CD—have you heard it?
This is the latest in a series of high-quality beauty products we offer you.
Have you heard the latest?  Ben is now going out with Jessica!

• We use last to refer to the most recent example, when no more will be produced.

Beethoven’s last symphony is my favorite one.
Who is the last person in line?
This is the last copy of Edgar Allen Poe’s Complete Works produced in his lifetime—it’s worth a good amount of money!

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