PKCS#12 is a file format used to store cryptographic keys and certificates securely. It allows users to bundle a private key with its associated public key certificate, making it easier to manage and transfer these sensitive materials. The format is commonly used for importing and exporting certificates and keys in various applications, such as web servers and email clients. Files in the PKCS#12 format typically have a .p12 or .pfx extension and are protected by a password. This encryption ensures that only authorized users can access the contained keys and certificates, enhancing security during data exchange.