Minecraft wiki entry for Version_formats, associated text: Beta reset the version number back to 1.0 after Alpha v1.2.6, and Beta version numbers now only had two numbers followed by an optional underscored bug fix patch (e.g., Beta 1.1_01 was released to fix a major bug in Beta 1.1). This format was inconsistent later in the Beta stage of development: for example, Beta 1.7 was followed by Beta 1.7_01 which was then followed by Beta 1.7.2. Beta also started releasing preview versions of major releases in the form of "pre-releases". These pre-releases took the form of the major version number followed by the word "Pre-release" and then a revision number. For example, Beta 1.8 Pre-release 2 was the second pre-release for Beta 1.8. Pre-releases for release 1.0.0, which was then called Beta 1.9, omitted the hyphen from the word "Pre-release". When it was decided that Beta 1.9 would be released as full version 1.0, future development versions were classified as release candidates, with RC1 and RC2 being the only ones.