Windows, Mac & Bootcamp Confusion

Ok, so I should start by saying I'm a windows user, and I'm simply trying to understand bootcamp. Ever since windows 8.1 I have started using my own heavily customised windows image as a starting point for any of my computers. It's a simple Macrium Reflect disk image. My first windows 10 image was created started by installing Windows from a CD to an SSD on a mac pro, then transferred that SSD to another computer where I made my changes, imaged, then deployed. When the Anniversary Update came around, it was large enough to break most of my changes so after leaving the update service turned off for far too long it came time to make a new image. Using a desktop I installed the new version of windows from a USB stick, and made changes in audit, imaged, deployed, and discovered 2 things. Somehow my old image was a single partition(System, Boot, Page File, Active, Crash Dump, Primary Partition) and the new install had created 4 partitions. Also, the Mac Pro was no longer able to detect or boot from the new version. I then decided to use bootcamp to perform the install, then make changes and image. When I did it that way it created a single partition(Active, Primary Partition). Now I'm just confused what is bootcamp? I always figured it was a tool to make the install process easy for mac users, but clearly it does something much more advanced. Is there a simple way to make a single partition image that can be booted from anything? Apologies for such a lengthy explanation.

What I see with Win10 is we had the 10240 RTM/Released version, then 3-4 months later we got the Version Upgrade [still called update] of 1511 then a year later we got the Anniversary Update or Version Upgrade of 1607. Now we are looking at another Version Upgrade most like Version 1703 [???]. The Builds appear to be a lot like a Service Pack and updates using a .xxx number are modifications added to the Build number. Each of the Version Upgrades have been large and pretty much gives the User a new OS so naturally some things will go back to Default. Some Build updates have done the same such as removing the old Win7/8 games that are available from some sites, probably because they are not actually part of Win10. One just has to keep their eyes open for that to happen and try to remember or keep records of their customizations/settings and re-apply them.

As to Partitions on an HDD or SSD such as System, Boot, Page File, Active, Crash Dump, Primary Partition, these will be seen in Disk Management. These are Defaults when installing Win10 on a new/clean drive.

Bootcamp, Parallels, VMware Fusion, et al, are programs used to install and boot different Operating Systems. I've installed VMware Fusion on a MacBook followed by Win7 but it wasn't a totally satisfactory solution for the client so she abandoned it when it wouldn't update Mac OS X sufficiently to run Win10, got a new iMac instead [quite nice]. Her MacBook is older than mine.
Boot Camp - Apple Support