Smile is scriptable, attachable (its objects have scripts), recordable and factored (internally scripted).
AppleScript beginners will find Smile an easy, comfortable and intuitive editor to make their first scripts. A "Guided Tour" provides an easy presentation of Smile, and the documentation available through the Help menu is thorough.
Smile fills Apple's Script Editor's main gaps: Search/Replace/Compare/Find definition; no 32k limit; drag-and-drop; and keyboard selection. It implements the most recent Apple technologies (Appearance, Navigation).
In addition it provides lots of tools to make scripting faster, easier, and safer.
Please read the documentation or visit the home page for more detailed information.
Smile is a PPC-only software. It uses Navigation Services and Appearance. Thus, it requires MacOS 8.5 or later. Mac OS 8.1 should work with Navigation Services installed. Earlier versions of the Mac OS also require the Appearance extension.