Cabinet-friendliness
Cabinet-friendliness is a classification of software in which every function is 100% controllable using a MAME-like arcade control interface. In the case of emulators or games, if the controls are able to be redefined to match MAME's, and the software requires no keyboard intervention, then it may be considered cabinet-friendly.
MAME-Like Controls
In MAME, the typical default keys for player 1 are: up, down, left, right, CTRL, ALT, SPACE, Left Shift, Z, X, 1, and 5 (coin); the default keys for player 2 are: R, F, D, G, A, S, Q, W, I, K, 2, and 6 (coin). Many keyboard encoders, such as Ultimarc's I-PAC 2 PC interface, are designed to be used directly with MAME, and therefore utilizes only these keystrokes.
Mouse-Controlled Software
Games which are primarily control by a mouse may be considered cabinet-friendly, due to the fact that cabinet builders often install a trackball assembly in the cabinet's control panel.