The archive contains some files :

• prototype-x.x.x.min.js : Minified Prototype JS
• scriptaculous-x.x.x.min.js : Minified version of scriptaculous containing builder,controls,dragdrop,effects,slider and sound components
• protoculous-x.x.x.packed.js : Packed version of Protoculous. The smallest of the package but can cause browser lockup at load time or at least can slow down the load time.
• protoculous-x.x.x.js : Regular version of Protoculous, bigger but recommended as it doesn't block the computer at load time

Pre-2.0 used some other tools (still listing on the left of this page) but due to the evolution of the Javascript, they are now obsolete