Purpose of subledger in AX 2012, posting of journals to general ledger

Hello everyone,

I have 3 questions,

-1- about different subledger in AX 2012, it seems the sub-ledgers are there, but they are not showing up much in the documentation. I heard they were more important in AX 2009, right now, what are they used for in AX 2012?

-2- And how are the sub-ledgers posted into General ledger, are all kinds of sub-ledger posted into General Ledger somehow?

-3- For the different Journal entries in different modules, are these posted to General ledger as well? I mean, for example, the invoice Journal in AP, payment journal in AR, Free Text Invoices in Sales & marketing, etc.

Thank you,

Kwen