<algorithm> (Or "message digest function") A {one-way function} which takes a variable-length message and produces a fixed-length hash. Given the hash it is computationally infeasible to find a message with that hash; in fact one can't determine any usable information about a message with that hash, not even a single bit. For some one-way hash functions it's also computationally impossible to determine two messages which produce the same hash. A one-way hash function can be private or public, just like an encryption function. MD5, SHA and Snefru are examples of public one-way hash functions. A public one-way hash function can be used to speed up a public-key digital signature system. Rather than sign a long message, which can take a long time, compute the one-way hash of the message, and sign the hash. {sci.crypt FAQ (ftp://src.doc.ic.ac.uk/usenet/usenet-by-group/sci.crypt/)}. (2001-05-10)

Grammar theory to model symbol strings originated from work in computational linguistics aiming to understand the structure of natural languages. Probabilistic context free grammars (PCFGs) have been applied in probabilistic modeling of RNA structures almost 40 years after they were introduced in computational linguistics.

In computing, a context switch is the process of storing the state of a process or thread, so that it can be restored and resume execution at a later point, and then restoring a different, previously saved, state.