A Java Keystore, often referred to as a “keystore,” is a file used to store cryptographic keys and certificates. It’s a critical component for securing and managing keys and certificates in Java applications. Keystores are used for various purposes, including:

1. SSL/TLS Communication: Keystores are commonly used to store server certificates and private keys for securing communication over SSL/TLS (Secure Sockets Layer/Transport Layer Security). This ensures that data transmitted between a client and a server is encrypted and authenticated.

2. Client Authentication: In some cases, a client application may need to present its certificate to a server for authentication. The client’s certificate and private key are stored in a keystore.

3. Code Signing: Keystores are used for code signing in Java applications. Code signing ensures that the software has not been tampered with and comes from a trusted source. Developers sign their JAR (Java Archive) files with their private key, and the public key is stored in a keystore.

4. Authentication and Authorization: In server-side Java applications, keystores can be used for user authentication and authorization. User certificates are stored in the keystore, and the application can verify the identity of users based on their certificates.