Sabermetrics (originally SABRmetrics) is the original or blanket term for sports analytics for the empirical analysis of baseball, especially the development of advanced metrics based on baseball statistics that measure in-game activity. The term is derived from the movement's progenitors, members of the Society for American Baseball Research (SABR), founded in 1971, and was coined by Bill James, (in 1980, according to SABR.org), who is one of its pioneers and considered its most prominent advocate and public face.

The term moneyball refers to the use of metrics to identify "undervalued players" and sign them to what ideally will become "below market value" contracts; it began as an effort by small-market teams to compete with the much greater resources of big-market ones.

English-American sportswriter Henry Chadwick developed the box score in New York City in 1858. This was the first way statisticians were able to describe the sport of baseball by numerically tracking various aspects of game play. The creation of the box score has given baseball statisticians a summary of the individual and team performances for a given game.

What would become the earliest Sabermetrics research in the 1970s and 1980s began in the middle of the 20th century with the writings of Earnshaw Cook, one of the earliest baseball analysts. Cook's 1964 book Percentage Baseball was one of the first of its kind. At first, most organized baseball teams and professionals dismissed Cook's work as meaningless. The idea of a science of baseball statistics began to achieve legitimacy in 1977 when Bill James began releasing Baseball Abstracts, his annual compendium of baseball data. However, James's ideas were slow to find widespread acceptance.

Bill James believed there was a widespread misunderstanding about how the game of baseball was played, claiming the sport was not defined by its rules but actually, as summarized by engineering professor Richard J. Puerzer, "defined by the conditions under which the game is played – specifically, the ballparks but also the players, the ethics, the strategies, the equipment, and the expectations of the public." Early Sabermetricians – sometimes considered baseball statisticians – began trying to enhance such fundamental baseball statistics as batting average (simply hits divided by at-bats) with advanced mathematical formulations. The correlation between team batting average and runs scored was also examined, as runs – not hits – win ballgames. Thus, a good measure of a player's worth would be his ability to help his team score runs, which was observed to be highly correlated with his number of times on base – leading to the development of a new stat, "on-base percentage".

Before Bill James popularized sabermetrics, Davey Johnson, then a second baseman playing for the early 1970s Baltimore Orioles of Major League Baseball (MLB), used an IBM System/360 at team owner Jerold Hoffberger's brewery to write a FORTRAN-based baseball computer simulation. In spite of his results, he was unable to persuade his manager Earl Weaver that he should bat second in the lineup. He wrote IBM BASIC programs to help him manage the Tidewater Tides, and after becoming manager of the New York Mets in 1984, he arranged for a team employee to write a dBASE II application to compile and store advanced metrics on team statistics. Craig R. Wright was another employee in MLB, working with the Texas Rangers in the early 1980s. During his time with the Rangers, he became known as the first front office employee in MLB history to work under the title "sabermetrician".

David Smith founded Retrosheet in 1989, with the objective of computerizing the box score of every major league baseball game ever played, in order to more accurately collect and compare the statistics of the game.

The Oakland Athletics began to use a more quantitative approach to baseball by focusing on sabermetric principles in the 1990s. This initially began with Sandy Alderson as the general manager of the team when he used the principles toward obtaining relatively undervalued players. His ideas were continued when Billy Beane took over as general manager in 1997, a job he held until 2015, and hired his assistant Paul DePodesta. During the 2002 season, a noted "moneyball" Oakland A's team went on to win 20 games in a row, a term (and approach to the game) which soon gained national recognition when Michael Lewis published Moneyball: The Art of Winning an Unfair Game (where "unfair" reflected the disparity in resources available to the big market teams versus the small) in 2003 to detail Beane's use of advanced metrics. In 2011, a film based on Lewis' book – also called Moneyball – was released and gave broad exposure to the techniques used in the Oakland Athletics' front office.