Is there a difference between Average Ledger balance and Average Daily balance??

There could be. There are two balances that are normally tracked in the banking world - the Average Ledger Balance and the Average Collected Balance (or Available Balance).

On the other hand, the Average Balance represents the sum of the daily balances over a specific number of days, so the terms that you posted could cover the same activity and produce the same 'average' result.

An "average daily" balance could be the average of the daily collected balance for the period or the average of the daily ledger balance for the period.

Your terms are not necessarily the same, and not necessarily different. It's like asking if there's a difference between cash and money. One term is more specific than the other.