The major types of System Softwares are:
Operating Systems (OS): The Operating Systems or OS are responsible for all the user friendliness of the computer. The OS runs and makes it possible for the users to interact with the computer without any knowledge about the underlying hardware. The OS interacts with the hardware using firmwares and device drivers and the users can use the hardware using the interface of the OS.
Boot Loaders: The boot loaders are small chunk of softwares that start up the operating system when the computer is turned on. They are the first instruction sets that the CPU processes. They help loading up the OS into the memory so that the OS can start and the computer is as usable as it is now.
Device drivers and firmwares: These softwares together help us use all the hardware devices like printers, cameras, flash drives, etc. The firmwares are softwares that reside on the device itself. They help the device hardware to function correctly and give results as it should. Device drivers on the other hand, are softwares that run on your computer's OS that help the OS to interact with the device firmware correctly.