The system software which manages the hardware and software resources of a computer is known as operating software. It acts as an intermediary between programs and computer hardware, particularly for hardware functions such as input and output, and memory allocation. Some of the different components of an operating system are kernel, user interface and computer network. Kernel, also called the core of the operating system, provides the most basic level of control over all the hardware resources in the computer. User interface, also known as a shell, is the component of the operating system which is integral for a human to interact with the computer. Command line interface and graphical user interface are the two major types of user interface. This book provides significant information of this discipline to help develop a good understanding of operating systems and related fields. It presents this complex subject in the most comprehensible and easy to understand language. Those in search of information to further their knowledge will be greatly assisted by this book.