Answer:
From a buyer's perspective, a sale made on credit represents a liability. While a sale made on cash represents a decrease of current assets.
From a seller's perspective, a sale made on credit or cash increases current assets, but the possibility of a bad debt always exist, therefore, accounts receivables must be periodically adjusted due to bad debts.
If the seller or buyer uses accrual accounting system, the previous description holds, but if they use cash basis accounting, things change a lot. When use cash basis, transactions are recorded only when cash is exchanged, so accounts receivables do not actually increase assets (seller's perspective), and accounts payables do not increase liabilities (buyer's perspective).