Most DVD rental companies provide the following variations of membership plans:
The unlimited rental plans have no maximum on the number of DVDs you can rent although there is a limit on the number you may have out at one time. The higher this limit is, the higher the monthly charge will be. You can keep the DVDs for as long as you want. But the longer you keep them, the fewer number of DVDs you'll be able to watch per month as your rental service will mail the next set of DVDs once you have returned the old ones.
The limited rental plans have a limit on the maximum number of DVDs that can be rented every month. There is also a limit of the number of DVDs you can have out at a time.
This type of plan allows individual rentals for a fixed fee with no monthly charge. You'll only pay a fixed price when you rent a single DVD. If you don't want the monthly cost, but you occasionally want to access the huge selection of online DVD rental services, this type of plan may suit your needs.