Posting/ Heading Account types - accountant/finance system question - Help needed!

[crabbitmaw]

Working on an import of data from one system to another. The one I currently use is very simple and the new one seems a bit more "financey".
One of the columns in my import template is "Account Type" and I need to choose from the below options. I have no idea what these mean and Google is giving me very ambiguous search results. One of the below options has to be assigned to each account in the general ledger so things like sales, wages, directors loan, postage, travel etc etc
1 Posting
2 Heading
3 Total
4 Begin-Total
5 End-Total

Its a very vague question without seeing it but I'd assume 1 is a date, (posting date) and the other 3-5 are values £, the only logical one it could be is no 2? Is that any use?

Although account type is likely to be: Revenue/ Expenses/ Assets/ Liability etc.

Thanks @LaWench Even more confusingly, there is a separate column (Account category) for assets/liabilities etc, as that is what immediately sprung to mind for me too. Unfortunately I don't think there is more info I could even give to help demonstrate it better. Its literally a blank excel sheet that I have to populate myself and the 1-5 is the only advice given for that column (Account Type)!

I'm using Dynamics 365 Business Central for a work promotion and after only half a day trying to get the basics down, I already think I've made a mistake! I've a list of questions as long as my arm 😅

Dont know the system but are you loading historic data?
Using journal uploads?

Posting could be month 1, month 2, this not the date field determines which month an amount is allocated to in management accounts.
Eg i have an invoice £1,000 which I sent out 15th May or month 5. My customer has come back to say that they need a credit note of £100 which I will issue today month 6. But for my aged debtor report I want to allocate that to month 5?

Heading can be an extra searchable detail field usually a short fixed field which allows a free form sub-classification. Eg multiple payroll entry (base bonus Bik) can be tracked by employee department so the system will allow you to group "salesEE" "storesEE" etc without having to search the HR files and YoY can be pulled faster.

The totals may be related to the periods if you are allowed to post multiple entries across multiple accounts and multiple periods
Eg rent allocation would be prepaid and split by department. So M1 bank, one month rent to each department and prepayment, then M2 M3 reversal of prepayment against the department.

Thanks @SolasAnla I appreciate such a detailed response. I understand some of it but sadly, not enough to implement it into to solving my problem.
The new system looks like it has great potential but it assumes an intermediate-expert level of both accounting knowledge and computing knowledge; I'm middling at best for both! I think I will need to go back to ground zero and see if I can find Youtube videos and the like of someone setting it up from scratch. I wonder if there is such a thing as "Dynamics 365 Business for Dummies" 😊