In software development, development stage terminology expresses how far through the development sequence things have progressed and how much further development a product may require.
Since this is the second major stage in the development cycle, following the alpha stage, it is named after the Greek letter beta, the second letter in the Greek alphabet.
In open source programming, version numbers or the terms "stable" and "unstable" more commonly distinguish the stage of development. In the Linuxoperating system, version numbers take the form of three numbers, separated by a decimal point. With regards to the second number, even numbers represent a stable release and odd numbers indicate an unstable release. The practice of using even and odd numbers to indicate the stability of a release has featured in many other open source projects.
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