Netezza: What schema contains all the system tables / views?
I don't know of a way to access such a list via a query but IBM provide a list of user views and system views in their Knowledge Centre. I assume those pages are public because their website tells me I'm not currently logged in (but it's not the most user-friendly of sites in terms of authentication so I may be wrong).

As CraigBoyd pointed out in a comment, SELECT * FROM _V_SYS_VIEW; will give you the list of system views. SELECT * FROM _V_VIEW; will also list some of the system views plus any user-defined views. I can't tell why some views are included in _V_SYS_VIEW but not in _V_VIEW.