What is an Operating system?
Simply it is the chief program which manages both software and hardware and acts as the connector of both resources. It has control of every process, file, all the sections of memory and device. It is also the interface between the user and the computer. Windows, Mac OS are some popular examples for paid Operating systems as well as Linux, Ubuntu is well known free operating systems. Also Android and IOS are the most populated operating systems used for smartphones. There are four essential managers of every operating system. They all work together as a team to make the job completed. Memory manager ,process manager, file manager and device manager are the four essentials. The memory manager is in charge of the main memory. It will allocate , reallocate and collect garbage of memory. The process manager decides how to allocate the central processing unit of the computer . and also it keeps track of each process and decides their states too. Device manager monitors every device and keeps track. It also makes the connection efficient with the hardware resources with the computer. File manager checks every type of file and keeps track on them which includes data files ,text files, executables files compilation files etc.
Services of the OS
Basically, OS is a layer of software which provides a great service to the computer system. Simply those services can be divided into two categories. Abstraction and arbitration.
Abstraction means hiding the details of hardware configurations so that the each application does not have to be tailored for the devices which it connects and has to possibility to connect. And also it provides the interface and the connection of the hardware devices manufactures by different users. So that the capability will be increased. Arbitration means the operating system simply manages the access to share the hardware components so that the multiple applications can run on the same hardware resources at the same time without interfering one another . The hardware resources include the central processing unit, the main memory, all the input-output devices and the power supply system.
Supporting any type of processor is an example for abstraction. Switching between applications can be defined as arbitration. Separating memory which was allocated for different applications is also arbitration.
What is the kernel of the OS?
More than the outside appearance of the operating system we see there are lot more functions and activities running inside. Kernel is the core of the operating system. Every multi-tasking computer uses this kernel in order to be a fully functional and efficient computer. Darwin kernel is mostly used in computer OS and Linux kernel is used in Android. Kernels can also be a proprietary and open source.
Kernel is the main manager of all the above-mentioned services and managements. All the signals, instructions, and services are managed and should pass through the kernel. This is the lowest layer which is above the CPU. Kernel also provides the necessary device drivers according to the detected resources. Also without the kernel the operating system will not be functioned efficiently and accurately.
So the operating system holds the main interconnection between the machine and the user. which does a greater job underneath the machine we see from the outside.
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