TwoPlusTwo:線上撲克遊戲研究資源網是世界上最大的線上撲克策略資源網站之一，不僅線上釋出撲克和遊戲資訊，而且出版撲克策略刊物，為使用者提供更多的撲克娛樂。

撲克是有著悠久歷史的有趣而複雜的遊戲。它起源於19世紀初新奧爾良中部和密西西比河流域的一種名叫Poque的遊戲。Poque只有20張牌，當舊規則為人們所熟悉時又演變出新的形式。Five-card draw、Five-card stud、Seven-card stud、Lowball、Hi-low以及後來的德州撲克和奧馬哈，就是撲克發展系譜中這些形式的其中一部分。隨著時間流轉，這種遊戲逐漸流行起來。

Two Plus Two Publishing LLC began in 1987 when Mason Malmuth self published his first book Winning Concepts in Draw and Lowball. These were quickly followed by Blackjack Essays and the original version ofGambling Theory and Other Topics.

In 1988, Mason and David Sklansky did their first collaboration and the original version of Hold ’em Poker for Advanced Players appeared. This was followed by Seven-Card Stud for Advanced Players (written with world class player Ray Zee) approximately a year later. Both of these books were self-published with demand surpassing all expectations.

Also, during the 1980s, all of David’s books had gone out of print. But by the end of the decade, David had retrieved the rights to them. These included Winning Poker (now known as The Theory of Poker) and the original Hold ’em Poker. At the end of 1989, David and Mason decided to unite all of their books under one “umbrella,” and a new company which for lack of a better name briefly became known as Malmuth Publishing.

A few months later, the 1990 edition of Gambling Theory and Other Topics was released. Since this book contained lots of mathematical equations, Mason felt it was important to have an equation on the cover. So starting with the original 1987 edition, the equation, 2 + 2 = 4, done with card pictures had appeared. But in 1990, the cover was redrawn by a professional artist. Upon seeing it, both David and Mason agreed that they had also found a much better name, and “Two Plus Two Publishing” was now officially in existence. (The LLC was added many years later.)

Today, Two Plus Two offers 35 different titles, all on poker/gambling, by 16 different authors including former World Series of Poker Champion Dan Harrington, Bill Robertie, Dr. John Feeney, Dr. Alan Schoonmaker, Nick Grudzien, Collin Moshman, and Donna Harris in addition to David, Mason, and Ray Zee. Many of these are recognized as the definitive works in their specific area or simply as instrumental in pushing the frontier of knowledge forward in their specific field. But a few beginner and intermediate books are also part of the mix. Total sales are now at 1,700,000 books and 250,000 of our Fundamentals booklets.