File systems of different devices and OS
File system determines the format of your device and serves as the means for allocating, storing and managing the data. File system is responsible for the way of storing and manipulating your files at the lowest level. File systems depend on the operating system and can be typical for certain storage devices.
Although file systems are flexible in terms of the storage to work on, typically a file system is chosen on the principles of appropriateness. Thus, you can still define the file system by a storage device.
As defining a file system by its storage is very general and respective, the operating system gives you a correct assumption. File systems are related to its operating system installed onto the storage. While file systems normally serve different purposes, an operating system may offer you more than one file system variant.
Based on HFS or HFS+.
It has a handful of file systems to meet your every need. Each of them has its own advantages and disadvantages.