[asterisk-users] usage of account code in CDR

[Sherwood McGowan]

Reposting my answer:
It's often used to signify an account that a call is associated with,
and I believe that was the original intent.

You can use it, however, to signify any important data about a call,
such as the pin number used to access a certain call feature (like
FreePBX allows you to do when restricting access to a route)