Operating Systems

1st you take two pieces of bread then you get the peanut butter and jelly and after that you have to put the peanut butter and jelly on the breadand then you enjoy your delicious peanut butter and jelly sandwitch

^ whoever wrote this(the above answer) is stupidu need to study the operating system because the operating system or OS is one of the most important thing on a computer without it the computer is just a piece or metal i might not be able to explain it all but at my answer is better than that of the above answer ^^^^

The operating system serves many purposes. Talking at a high level operating system can be cosidered as a translator between user and computer(CPU).CPU or processor can understand only 0s and 1s, but the programs that we use today are written in somehigh level language like C or Java or something else. Now these programs ultimately had to be changed to 0s and 1s inorder to execute. This is the responsibility of Operating System. Then comes multitasking, we can execute multiple programs simultaneously in a single CPU, so this single execution core is shared among programs. This CPU management is also onus of Operating System.Not only CPU managent but many other resources are managed by Operatimg System like memory. Speaking at low level you cannot imagine a computer without Operating System. To facilitate access to the workings of the machine, which at its core only deals in zeros and ones.
Without an operating system, you would have to manually type in instructions to the computer using machine code or a low-level language, and call functions.

It would take several hours to be able to perform simple tasks such as typing word documents!

Operating systems pre-load all the commands, information, and configurations the computer needs to perform tasks automatically, easily, and using a simple interface, such as mouse point-and-click or voice command, as well as streamlining general use and allowing simplified keyboard commands like control-alt-delete

The prime (and possibly only significant) difference is in the kernel scheduler, which determines which processes get run, with what priority, and for how long.

In a typical "ordinary" OS, the scheduler is some sort of "fair-use" implementation, which insures that no one process monopolizes all the resources if other processes are waiting for CPU time. That is, this kind of scheduler is optimized for interactive use, and the ability to make sure all applications run in a reasonable amount of time.

In a RT OS, all applications are given strict priorities, and the scheduler is designed to give certain characteristics to each priority rating. For instance, it is entirely possible for a RT scheduler to allocate all resources to a single process, and not give anything to any other process, until that process is complete (or does something like block on I/O wait). The based concept behind a RT OS is that certain process priorities are more important than others, and this importance is paramount over any concept of "fair" resource use. In essence, a RT OS prioritizes work in such a manner that certain processes can preempt others and hog resources in ways that a typical OS would consider extremely "unfair". RT OSes are typically optimized for embedded controllers, which are designed to require certain actions be completed immediately, regardless of other demands on the system.

Without security in a computer system you are violating the 3 tenets of security:

1. Confidentiality
2. Integrity
3. Availability

Embedded operating system

An embedded operating system is an operating system for embedded computer systems. These operating systems are designed to be very compact and efficient, forsaking many functions that non-embedded computer operating systems provide, and which may not be used by the specialized applications they run. They are frequently also real-time operating systems.

Examples of embedded operating systems could include the software used in Automated Teller Machines, Cash Registers, CCTV systems, jukeboxes, etc.

Features of Embedded Operating System

1-Embedded systems are designed to do some specific task, rather than be a general-purpose computer for multiple tasks. Some also have real-time performance constraints that must be met, for reasons such as safety and usability; others may have low or no performance requirements, allowing the system hardware to be simplified to reduce costs.

2-Embedded systems are not always standalone devices. Many embedded systems consist of small, computerized parts within a larger device that serves a more general purpose. For example, the Gibson Robot Guitar features an embedded system for tuning the strings, but the overall purpose of the Robot Guitar is, of course, to play music similarly, an embedded system in an automobile provides a specific function as a subsystem of the car itself.

3-The program instructions written for embedded systems are referred to as firmware, and are stored in read-only memory or Flash memory chips. They run with limited computer hardware resources: little memory, small or non-existent keyboard and/or screen.

Common features

The following table provides an overview of the features common to HP thin clients based on operating system using the following legend

3. Feature is fully functional and operates the same as the desktop environment.

2. Feature is partially functional and does not operate the same as the desktop environment.

1. Feature is barely functional and requires a highly skilled administrator to enable it.