It doesn't. There is no "mat" related to the game of English Billiards or Pocket Billiards.
In billiards the corner pocket means an opening in the billiards table into which the balls are struck into. There are also side pockets. the idea is to get the balls in to the pockets.
The balls are all equal from a points perspective in English Billiards, Carom Billiards, and Pocket Billiards.
There are generally two terms used for billiards - English billiards or pocket billiards. Pocket billiards is also called pool. Billiards is a popular bar game that has a number of different names that it has been called over the years but the most notable and popular is simply that of pool.
There is no "game billiards carom" but the question is presumed to refer to English Billiards, or 3 Pocket.
This depends upon which billiards game - English Billiards is most popular in the UK. Pocket Billiards is most popular in the US.
The are no values to the balls in either pocket billiards or English Billiards.
Billiards covers English Billiards, Carom Billiards, and Pocket Billiards, and each has their own set of rules.
Billiard balls can refer to the balls used for English billiards, pocket billiards, or snooker.