The game of softball was invented in 1887 in Chicago. Because it was originally played indoors, it was referred to as "indoor baseball" until 1926 when the game was officially called "softball." The name suggests that the ball is soft but, in reality, a fastpitch softball is as hard as a baseball. Slow pitch softballs can be slightly softer.
Due to softball's original indoor location, the original dimensions of its playing area were smaller than that of a baseball field. The size has remained constant: the bases, at the corners of a diamond, are 60' apart compared to baseball's 90'. Consequently, the distance from the pitcher's rubber to home plate is also shorter: 46' for men and 43' for women as compared to 60' 6" in baseball. Regulation fastpitch softball games are 7 innings long compared to baseball's 9.
Fastpitch softballs are slightly larger than baseballs and may be 11" or 12" in diameter. A baseball is about 9". When softball was invented, a 16" ball was used and the fielders did not use gloves. That tradition carries on today in Chicago. Fastpitch softballs weigh 6.5 ounces while baseballs weigh 5 ounces. While softballs may be white like baseballs, since 2002, the official color of the fastpitch softball has been "optic yellow," similar to tennis balls.
Unlike baseball, fastpitch softball bats may not be made of wood. Regulations require the bats be made of aluminum. (Fastpitch) softball gloves are slightly larger than baseball gloves in order to accommodate the larger softballs.
One of the obvious differences between softball and baseball is the way the ball is pitched to the batter. In fastpitch softball, the pitcher delivers the ball in an underhand, or windmill, motion. But the speed of the ball and the challenge it presents to the batter is amazingly similar to baseball! It's common for fastpitch softball pitchers to reach speeds of 60 mph or more with their throws. At the 1996 Summer Olympics, a pitch was recorded at 73 mph and, at the college level, speeds of 65-70 mph are common. Fastpitch pitchers can also make the ball move in many different ways like a baseball pitcher; pitchers at the high school level and higher can throw underhanded curveballs and sliders. Because the fastpitch softball pitching distance is 14" or 17" shorter than the distance for baseball, a softball traveling at 60-70 mph allows the batter about the same reaction time as in baseball. By the way, in both sports, the batter has about a half second or less to decide whether or not to swing!
Slow pitch softball is more widely played than the fastpitch variety. The pitches are slowly tossed at the batter in a high arc which makes contact easier. The game requires less skill to play than fastpitch softball. Moreover, rules may be modified to make the game more accessible to folks of all abilities and age groups.
At the collegiate level, the NCAA governs play between universities. From July 11-14, 2013, players from around the world competed in the 2013 World Cup Of Softball which is a fastpitch tournament involving 5 countries: Japan, Canada, the U.S.A., Puerto Rico and Australia. This was the eighth World Cup and the games were played in Oklahoma City, Oklahoma.
While a softball is slightly larger than a baseball, a fastpitch softball is not necessarily easier to hit. The shorter pitching distance, comparable ball speed and variety of pitches make the duel between the pitcher and batter of both sports very similar. There is a world of difference between slow pitch softball and baseball but the gap between fastpitch softball and baseball with regard to the pitcher/batter matchup is negligible.