[1] Skein was created by Bruce Schneier, Niels Ferguson, Stefan Lucks, Doug Whiting, Mihir Bellare, Tadayoshi Kohno, Jon Callas and Jesse Walker.

Skein is based on the Threefish tweakable block cipher compressed using Unique Block Iteration (UBI) chaining mode, a variant of the Matyas–Meyer–Oseas hash mode,[3] while leveraging an optional low-overhead argument-system for flexibility.

[5] The authors claim 6.1 cycles per byte for any output size on an Intel Core 2 Duo in 64-bit mode.

[6] The core of Threefish is based on a MIX function that transforms 2 64-bit words using a single addition, rotation by a constant and XOR.

Even a small change in the message will (with overwhelming probability) result in a mostly different hash, due to the avalanche effect.