This is the Definition of Free Cultural Works , and when describing your work, we encourage you to make reference to this definition, as in, "This is a freely licensed work, as explained in the Definition of Free Cultural Works ." If you do not like the term "Free Cultural Work," you can use the generic term "Free Content," or refer instead to one of the existing movements that express similar freedoms in more specific contexts. We also encourage you to use the Free Cultural Works logos and buttons , which are in the public domain.
It was not until the mid-1970s that encryption took a major leap forward. Until this point, all encryption schemes used the same secret for encrypting and decrypting a message: a symmetric key. In 1976, Whitfield Diffie and Martin Hellman's paper "New Directions in Cryptography" solved one of the fundamental problems of cryptography: namely, how to securely distribute the encryption key to those who need it. This breakthrough was followed shortly afterward by RSA, an implementation of public-key cryptography using asymmetric algorithms, which ushered in a new era of encryption.