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 inventor of billiards. The game evolved in Italy and France from the Italian game of trucco. The "father" of the game of billiards as we know it can best be attributed to Francois Mignaud 400 years after billiards was already an indoor game.