Turns were marked by the Danger Room Level, a sequentially increasing number that allowed cards of escalating power and effect to be played with each passing turn.

Since 1991, only 10,000 unskilled immigrants a year have been allowed green cards.

A column Binary option allowed cards with any combination of holes to be read and punched.

Different formats of Constructed Magic exist, each allowing different cards.

Modern allows cards from the 8th Edition core set and all expansion printed afterwards.

EMV was designed to allow cards and terminals to be backwardly compatible with these standards.

This allows cards from different fictional universes to compete and interact.

One of Reynold's early assignments was to develop technology that allowed cards marked with pencil marks to be converted into punched cards.

The F.B.I. also warned that Mexico's outdated databases allowed multiple cards to be issued with the same name, address and photograph.

In some small-form-factor systems, this may not be sufficient to allow even "half-length" PCI cards to fit.