Which algorithm published in 1993 is a software-based stream cipher?

FISH is recognized as a software-based stream cipher that was published in 1993. Stream ciphers encrypt data one bit or byte at a time, making them suitable for applications where low latency is crucial. FISH was designed to provide efficient encryption in software environments, aligning with the characteristics of stream ciphers that prioritize speed and efficiency.

RC4, while also a stream cipher and introduced in the same era, has a more prominent history and usage compared to FISH. DES and Twofish, on the other hand, are block ciphers, which operate on fixed-size blocks of data rather than incrementally like stream ciphers. Understanding these distinctions is important when classifying encryption algorithms and recognizing their intended applications.