A private key is a string of random hexadecimals (numbers 0 to 9 and letters A to F) that looks quite similar to a normal wallet address. This is created concurrently with a wallet address' creation and is usually given to you by your wallet service provider when you create a wallet address. However, depending on the wallet interface that you are using, you may or may not be given access to the address' private key (please refer to your wallet service provider for more information on this).

The private key signifies proof of your ownership over a wallet address and should NEVER be disclosed, exposed, or shared to anyone whether online or offline as doing so might lead to loss of funds. It should be stored somewhere safe (preferably offline on a piece of paper) where only you would know. Please take note that if a private key is lost, there is no way to either recover it or to regenerate it.