ITIL Outline discovered by Pat on Wikipedia:

I found some tid bits on Wikipedia in the ITIL section that may or may not be helpful (high level)

Release categories include:

Major software releases and major hardware upgrades, normally containing large amounts of new functionality, some of which may make intervening fixes to problems redundant. A major upgrade or release usually supersedes all preceding minor upgrades, releases and emergency fixes.

• Minor software releases and hardware upgrades, normally containing small enhancements and fixes, some of which may have already been issued as emergency fixes. A minor upgrade or release usually supersedes all preceding emergency fixes.
• Emergency software and hardware fixes, normally containing the corrections to a small number of known problems.

Releases can be divided based on the release unit into:

Delta Release: a release of only that part of the software which has been changed. For example, security patches.

• Full Release: the entire software program is deployed—for example, a new version of an existing application.
• Packaged Release: a combination of many changes—for example, an operating system image which also contains specific applications.