Data
The following data is compiled by the launch monitor after each shot.
-         Clubhead speed
-         Ball speed
-         Dynamic loft (loft of the clubhead at ball contact)
-         Launch angle (the angle the ball is launched when leaving the clubface)
-         Club head path
-         Clubface angle
-         Angle of attack of the clubhead
-         Rate of ball back spin and side spin
-         Displacement of the ball during and after flight
-         Carry and total distance
-         Efficiency or smash factor

How date is used to enhance the fitting process
The data from the launch monitor is particularly useful in fitting the driver club. Launch monitor is also useful in plotting incremental difference in shot distance between each club thus making it easier to work out the set make-up.
Traditionally it was believed that a ball that launched low and climbed higher during flight maximized shot distance when playing the driver. This method relied heavily on the ball roll after landing. Driver heads where designed with grooves consistent with iron club heads and were offered in lofts as low as 6 degrees. The problem here is that the main function of grooves is to encourage backspin. With the emergence of the launch monitor manufacturers and club fitters realized that a ball that spins too much creates too much drag against air resistance and hence the modern trend of offering drivers with higher loft and little or even no grooves began. Drivers with as much as 19 degrees are now available in the market.
The key to maximizing driver distance is to maximize carry distance. This is achieved by matching the ball launch angle and the backspin rate to the clubhead speed at impact. Simply the higher the clubhead speed the lower the launch and spin requirement. The lower the clubhead speed the higher the launch and backspin requirement. For example:
Clubhead speed of 100 mph requires a launch of 15 degrees and a backspin rate of 2400 rpm
Clubhead speed of 70 mph requires a launch of 21 degrees and a backspin rate of 3000 rpm

The optimum launch is achieved by matching clubhead characteristics such as loft weight and head design with shaft characteristics such as flex, deflection point and weight together with club length, total weight and swing weight (balance between the head and handle end of the golf club), together with your swing.
The angle of attack (or approach) of the clubhead to the ball is also a critical factor in maximizing distance off the tee. The angle of attack greatly influences the amount of backspin that is imparted on the ball at impact. It has been stated that the average attack angle on the USPGA tour is around 5 degrees and on the LPGA is around 8 degrees.

Testing shafts with varying shaft profiles during the fitting process aids the process of optimizing ball spin. Shaft manufacturers offer shafts with either low mid or high launch properties as well as high mid or low spin influences in many shaft weights. Typically slower swingers will be most suited to lighter, softer shafts with a high launch influence (low kick point) and faster swingers will be suited towards heavier, stiffer shafts with low launch influence (high kick point) however there are always exceptions.

History
The first launch monitor is believed to have been developed by Acushnet the parent company of Titleist Golf some back in the 1970’s. It featured a large mainframe computer with a camera that captured the ball and club at impact, and the ball about 12 to 18 inches into flight.
“Way ahead of its time,” Acushnet CEO Wally Uihlein said.
As with other advances in equipment, launch monitors are now portable, smaller and more efficient.

Types of launch monitors
There are currently two types of launch monitors in the market. One technology is using radar technology to track the ball its entire journey and the other uses high speed digital imagery of the ball and calculates the shot characteristics based on images immediately following impact. Both have their advantages however the radar systems do require more space in setting up. Perhaps the greatest thing about the expensive radar technology is that it confirms that the cheaper image based systems are in fact very accurate at calculating and simulating the actual ball flight and are a fraction of the price.
 
The Launch Monitor on Tour
 “There’s a lot of reasons the ball is going farther, and one of them is the launch monitor,” Jeff Sluman (PGA Tour professional) said. “You can really dial in the exact ball flight and get the right shaft and the right club, and that combination will maximize your potential off the tee.”
Brenden Pappas used a launch monitor for the first time two years ago while on the Nationwide Tour. He found the equipment for optimal launch angle and spin, and now tests himself every four or five months just to make sure his driver is reacting the way it should.  Pappas is tied with Tiger Woods at 10th in driving distance on the PGA Tour. “I’ve changed drivers to get extra spin on the ball,” he said. “If you don’t embrace technology, you fall behind. I use everything at my disposal. You’d be crazy not to.”

The launch monitor is not singularly responsible for players hitting the ball farther. It’s simply the catalyst for players being matched up with the best equipment — clubs, shafts, balls — for their game. “It shows players what it will take to play power golf,” said Bill Morgan, executive vice president of research and development at Titleist. “The information shows players how to make changes that give them increments of distance. For some, it was big. For others, it was not so big.”

Phil Mickelson showed at the start of his season in Phoenix how much he was putting that information to use. “The spin rate has been knocked down. The launch angle has been sent up. The ball is just taking on a whole different orbit,” he said in Phoenix. “From last year, I’ve got a 2-degree higher launch angle, 8 mph faster ball speed and about a 15- to 20-yard overall distance difference.”

Charles Howell III was still in junior high when he first went to the Callaway Golf’s test center and worked with a launch monitor. He came away with a lesson in engineering. “I learned that it was a lot of numbers involved in driving,” he said. “I had tried a bunch of different drivers. At that age, you’re just trying to hit the ball far, and you don’t understand why one driver goes farther than another. Now, you have numbers to put to it. I was lucky enough to have that when I was 13 years old.”

Dick Rugge, senior technical adviser for the U.S. Golf Association, believes the launch monitor simply speeds up the process of finding the right equipment. “It’s a catalyst,” he said. “It doesn’t create more distance, but it makes getting there quicker. Through trial and error, somebody could keep trying different clubs, balls and swings, and sooner or later they would get there. But the launch monitor makes it happen much quicker.”