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@xiaohe27 @yzhang90 and @kheradmand Please review some document changes
Yes, we are talking about building. I think that sentence makes sense because that "zip" or "tar.gz" are stable source code, and the user can unzip it to his/her favorite location  and then build it via maven right? I think it is just an alternative way of checking out the source code, though there might be some discrepancies: when the user check out the source code from the git, he/she can get the latest commit and the full commits history, and he can continuously update with git. If the users do not want to trace the development of javamop, then it is reasonable for him/her to use the stable source release.