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When Zong! was started in 2006 (back then called "Xenoage Score"), the versions were called px.y.z, e.g. p0.4.31. "p" stands for "pre-" (development version), x is the major version, y is the minor version and z is the sequential iteration number. In 2013, the Zong! was restarted, because it is now completely free software. The last version using the old numbering scheme was p0.5.63. Iteration numbering goes on with 64, but the major and minor version is reset and starts with 0.1-a.64 again.
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