2.4.1. Commercial and Community Driven Distributions
There are two main categories of Linux distributions: commercial and community driven. The former, developed by companies, are sold with commercial support services. The latter are developed according to the same open development model as the free software of which they are comprised.
A commercial distribution will have, thus, a tendency to release new versions more frequently, in order to better market updates and associated services. Their future is directly connected to the commercial success of their company, and many have already disappeared (Caldera Linux, StormLinux, etc.).
A community distribution doesn't follow any schedule but its own. Like the Linux kernel, new versions are released when they are stable, never before. Its survival is guaranteed, as long as it has enough individual developers or third party companies to support it.