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So first of all, what is a version
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control system? A version control system or VCS,
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is a system that allows you to manage
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multiple revisions of the same unit of information. For
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example of documents, of source files or any
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other item of that sort. And as the graphical
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depiction shows, a VCS allows a multiple actors.
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Here we have four, to cooperate and share files.
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Now, let's drill into this concept in a little
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more detail. And let's do that by discussing why
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is VCS useful, especially in the context of software
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engineering and of software development. So first of all,
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using a version control system enforces discipline, because it
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manages the process by which the control of items
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passes from one person to another. Another important aspect
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of VCS is that it allows you for archiving versions.
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So you can store subsequent versions of source controlled
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items into a VCS. And not only you can
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store versions, you can also maintain a lot of
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interesting and important historical information
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about these versions. For example,
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a VCL will store information such as, who is
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the author for this specific version stored in the system.
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Or, for another example, on what day and what
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time that version was stored. And a lot of other
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interesting information about the specific version of the
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item. Information that you can then retrieve and for
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example, use to compare versions. Obviously, the fact of
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having a central repository in which all these items
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are stored enables collaboration, so people can more easily
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share data, share files, share documents through the use
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of VCS. And I'm sure that you all had
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the experience of deleting a file by mistake or
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modifying a file in the wrong way, or in the
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most common case of changing something in your code for instance.
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And breaking something and not being able to go back
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to a version that was working. Not remembering, for example, what
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is that you changed that broke the code. In all
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these cases a version control system can be extremely useful because
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it will allow you to recover from this accidental deletions
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or edits. And for example, to go back of yesterdays version
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that was working perfectly, and also to compare, for example, yesterdays
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version with today version and see what is that you changed.
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Finally, a version control system will normally also allow you to
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conserve and save disk space on both the source control client
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and on the server. Why? Well, for instance because it's centralizing
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the management of the version. So instead of having many copies
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spread around, you'll have only one central point where these copies
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are stored or a few points where these copies are stored.
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In addition, version control system often
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uses efficient algorithms to store these changes.
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And therefore, you can keep many versions without taking up too much space.
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