It could be very debatable that in this day and age there are not that many companies, development shops, agencies or individual developers not using a strategy to keep different versions of the product (from now on I'm going to be referring to product rather than app, site, webpage to streamline the subject) isolated from each other depending on which point of the development process they are reflecting, but (and I'm quoting Mark Twain in this one) "truth is stranger than fiction...", and in this case truth refers to the reality of how the code for the product is managed.
