Assets & Liabilities

In this tutorial I'll try to give some more details about tagging cards.

By tagging a card we basically update properties of a Card. For example we can set a birthday for a customer card or set a table for a ticket. Tagging is the only way to set or change a value stored on a card.

A card may also represent a financial transaction. A financial transaction typically contains two types of information.

1. The asset that relates with the transaction.
2. Liabilty the transaction generates.

For example when we sell 1 Pizza it generates an asset transaction from an account (warehouse) to another so we can track how many pizzas we sold. If we also set a price for that transaction it also produces a liability amount. For example if the amount for 1 Pizza is 15.00 it means some account is obligated to pay $15 to us. Total liability amount a card produces is the total of card itself and the sub cards.

In above example we have a root Ticket Card and ticket card contains a sub Order Card. Order Card has 15.00 liability amount so Ticket Card has 15.00 balance.

A positive liability means it is Customer's liability and Customer has to pay us, negative liability means it is Our liability and we have to pay.

PM-POS determines if a liability amount is a positive or negative liability by looking at tag's Source and Target values. When Source tag is used it means we transferred an asset (1 Pizza) to customer (from kitchen). So customer has to pay us. If we use Kitchen as the Target it means 1 Pizza added to Kitchen account so we have to pay the amount.

For restaurant tickets it generally gets paid before customer leaves so storing customer account to track customer accounts is not needed. For table servicing it is still not needed. Storing the table name is enough. However if customer will pay us later we need to assign a customer name to track liability by customer. Fow now we assume customer pays ticket normally.

In this example we added another sub card under Ticket Card. Now our Ticket Card has 2 sub cards.

First one is the Order Card. It transfers 1 Pizza and generates 15.00 liability.

Second one is the Payment Card. This Card transfers Cash asset valued 15.00 to Wallet.Cash account. No quantity is used for Cash asset so it will generate no asset (inventory) transaction but the value of the asset is 15.00 so it adds 15.00 amount to Wallet.Cash account. As Target value is set for the tag this card generates a negative liability. (-15.00). The sum of +15 (1 Pizza) and -15 (Cash) makes 0 so there is no outstanding balance for the Ticket Card. That means card is balanced or in the other words Ticket is Paid. We expect no more payment or we don't need to pay back to customer so this ticket card can be closed.