Grains or grist?

[Iank]

Hi,
I've been reading loads on here and learning the techniques of AG, and looking at Daab's website, but there's something I'm not sure about.
The grains that you buy, like Maris Otter Malt. Do they come 'cracked' or do you need to somehow grind them in a mill to make them into grist? Is there a way of telling when you order them?
I'd feel pretty stupid attempting my first AG and finding I've not prepared the grains properly...

[Iank]

Thanks!