A fungo bat is used by the coach to hit ground balls or fly balls to his team. All throughout high school and college many players use fungo bats to play fungo golf. This is when each person has a fungo bat and a baseball and they pick out targets around their field or complex and basically play it in the same manner as golf. Fungo bats should not be used to hit a pitched baseball because they are much weaker than normal bats and will break much much easier.
Fungo bats typically weigh between 17 to 22 ounces and may be as long as 37 inches, making them longer than most bats used for hitting. According to Pro Bats, a typical professional baseball player uses a bat that is about 34 inches long and weighs about 32 ounces, although there is considerable variation. Fungo bats not only are longer than regular bats, they also are skinnier. Like regular bats, fungo bats can be made of metal or wood.
As I had previously mentioned, the amount of teaching points is limitless.  The length of the game will really depend on how often you stop the action in order to discuss points related to base running, backing up throws, fielding techniques, and etc.  If you have assistant coaches, have them distributed throughout the field in order to help with certain teaching points on the spot, thus eliminating full stoppages of the game.  Now get out there and start putting the “FUN” back into fungo. I know that’s pretty corny, but I couldn’t help myself 🙂
Versatile fungo bats are the ones tailored for both outfield and infield practice. Infield bats are effective for those that desire to rip their ball to the young ball hawks. These bats are thicker and heavier through the center in order to give you more oomph. Thicker bats work better especially to softball coaches to hit bigger balls utilized for softball.
The origin of the word "fungo" is unknown and argued upon as there are many possible options as to the origins of this unique word. It is assumed by many to be derived from the Scottish word fung meaning to pitch, toss, or fling. This would make sense, as fungo bats are designed to do just that. Or, the alternative to this origin is that fungo comes from 1937 where David Shulman, writer for the American Speech, said, "My guess is that the word, which is baseball slang, may be explained through the elements of a compound word, fun and go." Lastly, a third belief is that the word fungo comes from an old game, similar to that of baseball, where the players used to chant, "One go, two goes, fun goes." 
While many people view the fungo bat more as an antique piece of baseball’s history, there’s no doubt that it still has a special place in the modern game. Actually, the bat is starting to enjoy some revival all-round the game. Regardless of minimal production of fungo bats, you can rest assured that they’re here to stay. The bats are too beneficial to both coaches and players on a daily basis.
This is the drill we ran all through high school. It is the most time effective and skill intensive way to warm up a team, but your boys must be able to play catch! Fungo-ers stand in the "fungoe circles" that any good field has (and if it doesn't, you know where they're supposed to be - just outside of the home-plate dirt circle, towards the dugouts). The catch to this method is this - you have two first basemen, allowing both sides of the infield to throw across. Herein lies the only danger - one of the firstbasemen has a lengthy throw back to a shagger, so caution must be excersized (a catcher with a good head on his shoulders really helps).

Players can be very particular about their bats. Ted Williams cleaned his bats with alcohol every night and periodically took them to the post office to weigh them. "Bats pick up condensation and dirt lying around on the ground," he wrote, "They can gain an ounce or more in a surprisingly short time." Ichiro Suzuki also takes great care that his bats do not accumulate moisture and thus gain weight: he stores his bats in humidors, one in the club house and another, a portable one, for the road. Rod Carew fought moisture by storing his bats in a box full of sawdust in the warmest part of his house. "The sawdust acts as a buffer between the bats and the environment," he explained, "absorbing any moisture before it can seep into the wood."[25]

Another variation of playing is setting a target (i.e. home plate), and that is the hole for the entire game. For the entire game players go to a different part of the field and try to hit home plate in the fewest strokes.To make the game more interesting players can create certain hazards or obstacles that the players must avoid hitting while making their shot. If a player hits a certain hazard then they may be penalized one stroke, a player can also lose a stroke if he loses their ball while taking a shot.