What is the difference in usage between "for instance" and "for example"?

What is the difference in usage between for instance and for example?

Are they just interchangeable? I suspect they are not strictly but cannot seem to find an authoritative explanation.


Solution 1:

according to this link: http://forum.wordreference.com/showthread.php?t=152653

  1. I would hear for example to refer to a particular type of occurrence where many types exist.
  2. And I would hear for instance to refer to a particular occurrence of the same type, where many occurrences exist.

The auditors look for many types of fraudulent activity, for example, reporting revenue from fictional sales. Implying there are other types of fraudulent activities.

Another Example

Mr X is being investigated for wash sale rules violations, for instance the trade with ABC Corp where he bought the same shares in his personal account from DEF Corp. Implying there are other violations of the same type, i.e. wash sale violations, and this is just one instance/occurrence.