The core of an operating system is called the kernel. It forms the basic code around which the OS is built and provides the basic functionalities such as memory management, interrupt handling and input/output handling. It manages the input and output requests from software and translates them into CPU instructions and instructions to the electronic components of a computer. Some of functions and tasks of the kernel are:

• Executing processes
• Handling interrupts
• Memory management
• Managing the address space
• Interprocess communication
• Central processing unit instructions processing and allocation
• Random access memory management
• Input/output device management

The tasks performed by the kernel are carried out in the kernel space whereas the operations carried out by GUI and other user applications are carried out in user space.

In the case of Windows operating systems beginning with Windows 95, kernel32.dll runs as part of the kernel module. It is one of the files required for the proper functioning of the Windows OS. This kernel is most widely known due to error messages that users see when something goes wrong with it. Faults or errors caused in the kernel32.dll file can cause Windows to malfunction or not work at all.