In ancient Greece, an enchiridion was a small, portable book that gave information about one specific topic. A new car usually comes with its own enchiridion.
Enchiridion is derived from the Greek enkheiridios, "that which is held in the hand," from kheir, "hand." Imagine a small handbook or manual that would fit in a tote bag or large pocket — that's an enchiridion. The first of these were written by ancient Greeks on topics including ethics, law, and the writing of poetry. But if you want to impress, you can describe the manual that comes with a new blender or television as an enchiridion.