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MAJOR version changes are made when significant new features are introduced. Usually, these new features are visible to the user, but occasionally they may just be significant improvements under the hood. Changes may include breaking changes, but if so, this will be clearly stated in the release notes.
MINOR version changes are made when new features or improvements (or both) are introduced, which should be fully backward-compatible.
PATCH versions do not include any new features or improvements, but only fixes of what we have considered unintended behavior (commonly referred to as bugs).
PATCH versions continue to support the same minimum version of the Atlassian platform, even if it has reached end of life, to make sure they can be used to update previous PATCH versions.
MAJOR and MINOR versions may always also include bug fixes.
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