T+1 trade settlement
T+1 is a trading regime where you make a deal today and the settlement is made on the next working day.
Let's say you bought the securities on Monday. Then they will be credited to your account on Tuesday after the close of trading. The same applies to the sale of stocks. After the sale transaction, the money is credited to your account and becomes available for withdrawal only on the second working day.
T+2 trade settlement
T+2 is a trading mode in which you enter into transaction today and settle within two business days.
Likewise, let's suppose that you bought a stock on Monday. In the T+2 trade settlement mode, you will become the actual owner of these shares on Wednesday after the close of the trading session, that is, on the third business day.
The settlement mode should be taken into account for non-trading transactions on the brokerage account, such as conversion and withdrawal of funds, as well as when it is necessary to receive dividends.