Basically these are collector items in the vein of Pokemon Cards and Magic Cards, but predates all card based collectables. Like magic and pokemon cards, baseball cards contain statistics, but unlike magic and pokemon cards, the players with which these statistics refer to are real and not imaginary like players dipicted in magic and pokemon, which are made up to serve gaming purposes. Thus, baseball cards are not gaming cards and serve only to amuse and pleasure those who love baseball and their players (See keedon, baseball).
That damn keedon got so obsessed with getting that Ken Griffey Jr. baseball card that he flunked his midterms and got me to do his homework. Damn him and his obsession with baseball cards!!! (See keedon).
A baseball dad is a middle-classed man who spends his time at the bars and taking the kids to sporting events in his new pick-up truck. He never lets his kids watch TV shows or movies that are PG-13 or contain "foul language", and spends a lot of time are beer pong parties, and smashing copies of GTA.
Middle-classed men who usually drive pickup trucks, ban their kids from watching showing with swearing in it or anything PG-13, ground their kids all the time or take away their electronics frequently, and attend sporting events such as football, or baseball (hence the name) and making them chop wood in the morning.