A partition is a part of a hard drive that the operating system treats as a separate hard drive. Simply explained, virtual A/B partitions mean both smoother and safer system updates which, among other things, mean that – if an update goes wrong – it is possible to return to the previous version. Google already introduced the feature in Android 7 Nougat. According to XDA, the reason that many mobile manufacturers have not previously used it is because they do not want it to take up extra hard disk space.
By making updates smoother and safer with A/B partitions, Google believes that there is a greater chance that more users will update their software more often. Which also means that more users will also have the latest security updates.
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