The Courts Themselves
"...the shadows are like frayed curtains in the Courts--often, you can look right through into another reality without even trying..." --Merlin, Prince of Chaos
Probably the easiest way to think of the composition of the Courts of Chaos in a way that's understandable to someone used to more "conventional" physics (those of Amber or Shadow Earth, for example) is by means of this metaphor:
Imagine a big cluster of bubbles, clinging to each other. Each one of these bubbles is one of the Ways. Each Way represents one of the dwelling-places of a House of Chaos (the Ways of Sawall or the Ways of Hendrake) or, sometimes, that of a particularly powerful individual in Chaos (Mandorways, the Ways of Suhuy).
Within each of these bubbles are many smaller bubbles: each Way is stitched together from many different pieces of Shadow, rather like a patchwork quilt, to form interlinked byways. Some are very stable and easily navigatable, whereas others shift constantly and can be navigated only by the very knowledgeable.
The largest bubble of the cluster lies at the centre. This is the Courts part of the Courts of Chaos, a relatively stable area containing communal buildings of importance like the Cathedral of the Serpent and the king's palace, Thelbane, both of which stand near the Abyss within the Plaza at the End of the World.
Passing from one Way to another is a matter of knowing where to go (and sometimes when to go, or what to bear when you're going, or...). In most cases, you can find a route from any one Way to another Way with some searching or the proper knowledge, and all the major Ways generally have direct connections to one another, if not necessarily ones that are generally known. Many of the ways are also connected in places to points in Shadow, in the Black Zone, or even further away.
This whole cluster of bubbles hangs above the Great Pit, the Abyss of Chaos. Occasionally, an unstable or weak bubble will drop off and vanish into the Pit, lost forever; just as occassionally, the Pit will belch up raw material which an enterprising House or individual will seize on and use to increase the size of their particular bubble.
Given the whole arrangement, time and space and distance and such tend to be very funky in the Courts. This metaphorical explanation is somewhat simplified and fails to give the whole picture, but it's a good general model.
The Black Zone
The Black Zone is Chaos's equivalent of the Golden Circle, a political alliance of nearby Shadow kingdoms associated with the Courts. Given the nature of the Courts compared to Amber, Black Zone countries tend to serve more as vacation spots and hiding places than as actual trade partners, and the Black Zone is held together less by careful politicking than by a collective fear of the might of the Courts.
A big mess. There are over a dozen major Houses of Chaos, and at least a hundred minor ones, most of whom are allied in a kind of vassal relationship to one of the major Houses. The Houses vie with each other constantly for even the smallest scraps of political power... or at least, they used to. Ever since King Swayvill's miraculous recovery two decades back and the subsequent purges that followed due to his displeasure at the shady and murderous activities that had gone on during his illness, the Houses have tended to be understandably less eager in their activities, and more afraid to incur the king's possible displeasure. Power has thus become increasingly centred on the Royal House of Swayvill, and hardly to the pleasure of most of the powerful Houses.
Notable Houses of Chaos include the following:
The Royal House of Swayvill
Other Houses (non-canonical), of import to the game