Why Are Subsidiary Ledgers Necessary And What Is Their Relationship To The General Ledger?

What is the point of a subsidiary?

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What are the two common examples of a subsidiary ledgers?

Why subsidiary ledger is important?

What is general ledger and sub ledger account?

What is the relationship between an accounts payable subsidiary ledger and the accounts payable general ledger account?

How does the subsidiary ledger and general ledger stay in balance?