P12 - Personal Information Exchange File
This is a file containing a digital certificate using the PKCS#12 (Public Key Cryptography Standard #12) encryption scheme. It is used as a portable format to transfer personal private keys as well as other sensitive information. P12 keys contain a private key which can be used to encrypt information that can only be decrypted with the corresponding public key and data encrypted with the public key may only be decrypted with the private key. This helps to verify and validate transmitted data and its sources.