The most basic skimming scheme occurs when:

An employee sells goods or services to a customer, collects the customer’s payment, but makes no record of the sale.

An employee buy goods or services from a customer, drop the customer’s payment, but makes no record of the purchase.

An employee sells goods or services to a stakeholder, collects the stakeholder’s payment and makes record of the sale too.

An employee buy goods or services from a stakeholder, drop the stakeholder’s payment and makes record of the purchase too.