Many, many years ago, in my first tech job, we had an early, proprietary CMS (content management system) for websites in a particular industry. The software was written in C and installed on the company’s servers. The structure could be compared to an early Wix or Weebly.
But every time, there was an upgrade to the server software, the C code would have to be recompiled to run with the new operating system. This is what is meant by an incompatibility. The new version of the operating system was not compatible with the old compiled code. But, it could all be taken care of by the in-house programmers. The software only had to be updated on one system … and it was internal.
In CS grad school, Dr. Joel Henry taught us about the extra steps needed to create off-the-shelf (OTS) software. This is a situation where the software vendor has an online download or the software is delivered on some storage like DVD. The person doing the install may not understand the install process. It just needs to work … on all systems.
It might seem like the installer would be considered part of the original software, but actually, it’s not. It’s like the hoses used to connect your dishwasher into your plumbing aren’t actually part of the dishwasher.
Review of 4 installer packages : I have not used any of these, so I cannot provide first hand information. But, pursuing this article will help you understand the topic further.