[Kaiba had to stop himself from shooting her an incredulous look, and remarking with something smart. There was a reason he generally didn't associate with amateurs, but.. now he had to.

Taking a breath.]

... they're... a large... part... of it.

[Along with all the other cards in a deck.]

You play the cards on what's called a field. The field consists of 14 slots. 5 are reserved for monsters, 5 for spells and traps, then one for any field spell, one for an extra deck, one for the graveyard- where cards are discarded after being used or destroyed -, and one for the deck itself.

I'd suggest a practice game.. since it's easier to learn through experience.