When a transaction is not yet confirmed by the merchant it is pending.
In certain situations, the merchant where you purchased a good or service can withheld balance. It means that it can block a certain amount before confirming the transaction. This can occur because the merchant wants to be sure that you have funds to pay the goods or service. This can happen when you book an hotel or when you request food delivery, for example. It also happens with payments abroad that will be first registered as pending transaction and later confirmed.
If a pending transaction is confirmed it will be updated in your Feed. If the transaction expires or it is canceled (what can take up to 10 days) it will be eliminated from your Feed and the amount will be available in your account.
Pending transactions will be immediately deducted from your balance. You can only split, send to Group or change the category after the transaction is confirmed.