What is a single purpose certificate commonly used for?

A single purpose certificate is specifically designed for a particular function or use case, and in this instance, it is commonly used for signing code. Code signing certificates enable software developers to sign their applications, assuring users that the code has not been altered or corrupted since it was signed. This process helps build trust and ensures the integrity and authenticity of the software being distributed.

When a code signing certificate is applied, it binds the identity of the software publisher to the code that is being deployed. This not only provides assurance to users about the origin of the software but also helps prevent malicious activities such as code tampering.

Other options entail functions that can require different types of certificates. Encrypting user data typically involves encryption certificates, verifying email authenticity is usually achieved through email signing certificates, and storing user information is not a primary purpose of single purpose certificates. Each of these functions either overlaps with different certificate types or has broader applications, which is why the focus on code signing for a single purpose certificate is particularly relevant.