Post trial balance?

What is a permanent account

A permanent account is one that keeps its balance going into a new accounting period, as opposed to one that closes out and starts over at zero.

Revenues, expenses and drawing/dividend are temporary accounts. For instance, if you have revenue, you want to know what it is for this year, and you don't want it accumulating year after year. Just like your paychecks -- they start over at zero each year, and you need for the amount to be contained within one year.

Whereas something like a cash account doesn't start at zero for a new year and accumulate throughout the year. It comes and goes, and it has a different balance at any given point in time. At the end of the year, it will have a balance, which needs to carry through to the new year. If the company has $10,000 in cash, then they actually do have it, and it doesn't net back out to zero just because a new year started. All asset and liabilities are permanent accounts. And most equity accounts are permanent also.

As for "post trial balance?" -- what exactly is the question? That's a thing, not a question.