Drop Pods are launched directly from SMC starships into their intended landing zone. As they fly through the atmosphere, each pod can use its four stabilizing fins at its end. Even though it is never seen, it is likely that the Marine inside can manually guide it to a certain extent (there's a control stick to be seen in the Quake 4 models). After impact, the front plate is blasted away and the Marine can leave it.
While the drop pods seen in Quake 2 bear the Marine's name, most of those shown in Quake 4 sport no individual markings. However, there are some pods with a circular picture and a parole on their front plates.
When compared to SMC dropships, the Drop Pods seem to be faster and can be deployed more easily as the Pods are simply shot from a SMC spaceship. Furthermore, prop pods are capable of penetrating the walls of buildings; therefore, they can be used to insert Marines into highly guarded facilities that would have to be stormed first if a dropship was used.
The Drop Pod has some disadvantages over the use of dropships: whereas the latter are far more versatile and can transport up to ten Marines as well as cargo, each pod is only able of carrying one Marine. As the Pod's interior is very cramped, the pilot can barely stow a weapon in it, let alone further (important) equipment. Also, the Pods are designed for single-use only and cannot return from the ground on their own. This makes them only practical in missions where the Marine using it has backup, otherwise he would be stuck deep behind enemy lines, or when this is the first wave of an invasion and so extraction is not needed.
Despite being quite fast, the Pods can still easily be shot down by anti-aircraft weapons as they are not as heavily armored as a dropship. They are also not small or well-shielded enough to avoid being detected and survive the Big Gun's EMP. When the Pods are hit by an EMP charge, the pilot loses control or the on-board automated guidance system completely malfunctions, leaving the Pod as little more than a falling metal coffin. In Quake 2 and 4, some of the Drop Pods never reach their objective due to being shot down or catching fire.