Got this off Wikipedia....helps a little at the end.
Uses and Doctrine
Glider infantry were loaded into gliders at friendly airfields. They where then attached to towing aircraft by a cable. The now loaded gliders where then towed through the air to a release point usually just beyond the hearing range of enemy troops. The tow cables were released and the gliders would be piloted, unpowered, to a designated landing zone. The glider was landed and the troops and equipment would disembark and enter combat. Glider pilots were often organized together after landing to fight or be extracted to safety.
Compared with paratroops, alongside whom they would operate, glider-borne troops had several advantages:
Gliders could carry and deliver much bulkier and heavier equipment than powered air transport at the time. Thus glider infantry units were usually better equipped than their parachute infantry counterparts.
Any one stick of glider infantry could disembark intact and combat ready in contrast to paratroops which needed time after landing to regroup and reorganize before beginning operations. Under ideal conditions, whole glider units could land intact also.
Unlike drop planes which delivered paratroops, gliders were totally silent and detection by the enemy was difficult which greatly added to the element of surprise. In fact, completely undetected insertions were possible. This was especially true for night landings.
Glider infantry required much less training than parachute infantry. In fact many glider infantry units were simply converted from regular infantry units with only cursory training.
However using gliders as a method of insertion also had serious drawbacks:
Gliders required a relatively smooth landing area free from obstructions. A common countermeasure against gliders was to sow posts and other obstructions in likely landing areas.
Gliders were fragile and glider landings were rough and brutal affairs. All too often, gliders were destroyed during landing attempts, killing all the passengers.
In practice, it was difficult for entire units to land together and glider-borne units often ended up even more widely scattered than parachute units.
Gliders and towing planes were extremely vulnerable to interception by enemy aircraft while gliders were under tow. Gliders were also hapless against ground fire if they were detected before landing.
Glider pilots were expensive to replace and were often killed.
In both the British and American armies, there was a sense that the glider infantry were poor cousins to the more glamorous paratroopers. In the British Army, whereas paratroops were volunteers, airlanding units were line infantry units converted without any option. In the US Army, glider troops did not receive the extra pay awarded to paratroopers.
In one respect the armies differed. The British Glider Pilot Regiment were not only trained aircrew, but also well-trained infantry, most of whom would have been junior or senior NCO's in other units. By comparison, the American glider crews were treated on the same basis as non-combatant drivers.
The Allied gliders used were mass produced. Three aircraft dominated, the American Waco CG-4A which could carry 13 passengers, the British Airspeed Horsa, which could carry 25 passengers, and the British General Aircraft Hamilcar, which could carry up to eight tons (8,000 kg) of equipment.