OpenSSL is an open-source implementation of basic cryptographic primitives, X.509 certificate utilities, and SSL and TLS protocols.

OpenSSL is an open-source implementation of the SSL and TLS protocols. It is written in C and it implements basic cryptographic functions. Wrappers are available for a wide variety of computer languages.

For the typical security developer, openssl is the go-to library/API for cryptographic operations, certificate-related utilities, and SSL/TLS implementations. Openssl has a reputation of being reliable and fast, and is often considered to be the reference implementation that other crypto implementations are checked against.

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