ERC-20 tokens commonly expose two values that can look related but answer different questions: balance and allowance. A balance is usually read with balanceOf(address). It reports how many token units the token contract currently records for that address. If an address has a balance of 50, the contract's ledger says that address holds 50 units at that moment. An allowance is usually read with allowance(owner, spender). It reports the remaining amount that a particular spender is authorized to us

In a crypto order-book market, trading volume and liquidity are often discussed together, yet they answer different questions. Volume records trades that were completed during a defined period. Liquidity describes how readily an order may be matched near prevailing prices at a specific moment. One is a record of activity; the other is a condition of the market. Order-book depth is a practical view of liquidity. It lists resting buy orders, called bids, and resting sell orders, called asks, acros