Billiard table ivory balls from warping. The first use of electric heating was for an 18.2 balkline tournament held in December 1927 between Welker Cochran and Jacob Schaefer, Jr. The New York Times announced it with fanfare: "For the first time in the history of world's championship balkline billiards a heated table will be used..." A pool table, or pocket billiards table, has six – one at each corner of the table () and one at the midpoint of each of the longer sides ( or ). Pool tables come in different sizes, typically referred to as , , , or tables.
Billiard Congress of America dates, and some debate surrounded the matter, with the dates being finalized only as late as September 2009, and chosen to ensure maximum attendance by billiard entrepreneurs, most of whom have business peaks on weekends. By the end of the 2009 Expo, 65 companies had already contracted for 326 booth spaces at the 2010 Expo. The vast majority of attendees are industry insiders, rather than players. In 2006, 94% were billiard retailers, 5% billiard hall operators, and 1% "other" (e.g. bowling and amusement center operators). In 2009, only 70% were retailers. In that year, 83% were from the United States