I'm wanting to learn sugar and plan to do some work on both the newest and 6.5 ce versions. Which version of the documentation do you suggest I read or are the systems different enough that I'll basically need to read both?
Documentation for version 6.5.x CE is no longer available, so you would need to look at this article. This is related to version 8.0, that means only few topics are compatible to version 6.5, like:
6.5 documentation (and all unsupported versions since 6.0) can be found here:
I strongly recommend that you review documentation for 6.5 and the most recent release as there are drastic differences between 6.5 CE and the current iterations of Sugar.
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