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Something else I want to mention is that there
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are many different version control systems but we can classify
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them normally in two main types: centralized VCS's and
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decentralized VCS's. So what is the difference between these two?
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Let's use again our friends Janet and Brett.
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In the case of a centralized version control system
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there is a single centralized, as the name says,
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repository. On which they are commiting their files. So when
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Janet commits a file. The file will go from
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her local working directory to the repository, and the same
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will happen to Brett. The decentralized system is a little
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more interesting because in this case, they will both have
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sort of a local repository in which they can commit
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their changes. So they can commit changes without the other
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users of the VCS being able to see these changes.
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And when they're happy with the version. And when they're
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ready to release the version, they can push it to a central
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repository. And at that point, it will become available to the other
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users of the repository. To the other users of the VCS. There
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are several advantages in a distributive
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system. I'm just going to mention a few,
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because there are really many. One is the fact of having this
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local version. If you used VCS before, I'm sure you've been in
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the situation in which you want to kind of take a snapshot
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of what you have. But you don't want that snapshot to be available
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to the other users. Because it's still not ready to be
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released, to be looked up. If you're using a centralized system,
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there's really no way you can do that, unless you make
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a local copy, which is something we said you don't want
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to do. With a distributor, with a decentralized VCS you can
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commit your local changes here, in your local repository, and you
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can push them to the central repository only when you're ready.
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Another big advantage, is that you can use multiple remote repository.
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In fact, centralized is not the right name for this
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one. This is just a remote repository, and I can have
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more than one. For example, Brad might want to push
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to another remote repository. As well. For instance, this could be
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a repository where the files are accessible for wider distribution.
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Imagine developing a software system in which a team is sharing
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internal versions, and then only some of these versions are actually
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pushed to the repository that is seeable to the whole world.
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