Alpha：
Alpha is an internal beta version, generally not released to the outside world, there will be many bugs. Unless you are also a tester, it is not recommended to use it. It is the first of the Greek letters, indicating the most advanced version, alpha is α, beta is β, The alpha version is the beta version that is earlier than the beta version, which is generally the version for internal testing.
Beta:
Compared with the alpha version, this version has been greatly improved, and serious bugs have been eliminated, but there is still a defect that needs to be further eliminated after many tests. This stage of the version will always add new features.
RC: (Release Candidate)
Candidate means candidate, and it is a candidate version when used in software. Release.Candidate. is the release candidate. The biggest difference from the Beta version is that new functions will always be added in the Beta stage, but almost no new functions will be added in the RC version, and the main focus is on debugging! The RC version is the closest to the official version that is finally released to users. The version that corrects the bugs after the release is the official version, which is the last beta version before the official version.
GA: (general availability)
For example: Apache Struts 2 GA This is the first stable version of Apache Struts 2, GA means General Availability, which means that the official began to recommend widespread use.
Release:
This version means "final version". After a series of beta versions of the previous version, there will eventually be an official version, which is a version that is finally delivered to users. This version is also sometimes referred to as the Standard Edition. Normally, Release will not appear on the software cover as a word, but instead is a symbol (R).
Transfer: http://blog.csdn.net/zmken497300/article/details/51707967