Firmware is a program or set of computer instructions stored in the physical circuitry of ROM memory. These types of programs are typically changed infrequently or not at all. In servers and user workstations, firmware usually stores the initial computer instructions that are executed when the server or workstation is powered on; the firmware starts the CPU and other onboard chips, and establishes communications by using the keyboard, monitor, network adaptor, and hard drive. The firmware retrieves blocks of data from the hard drive that are then used to load and start the operating system.
A computer's BIOS is a common example of firmware. BIOS, or Basic Input-Output System, contains instructions needed to start a computer when it's first powered on, initialize devices, and load the operating system from secondary storage (such as a hard drive).
Firmware is also found in devices such as smartphones, tablets, DSL/cable modems, and practically every other type of Internet-connected device, such as automobiles, thermostats, and even your refrigerator.
Firmware is typically stored on one or more ROM chips on a computer's motherboard (the main circuit board containing the CPU(s), memory, and other circuitry).
Software includes the operating system and programs or applications that are installed on a computer system.
A computer operating system (OS) is the software that controls the workings of a computer, enabling the computer to be used. The operating system can be thought of as a logical platform, through which other programs can be run to perform work.
The main components of an operating system are:
• Kernel: The core component of the operating system that allows processes, control of hardware devices, and communications to external devices and systems to run.
• Device drivers: Software modules used by the kernel to communicate with internal and external devices that may be connected to the computer.
• Tools: Independent programs that perform specific maintenance functions, such as filesystem repair or network testing. Tools can be run automatically or manually.
The operating system controls a computer's resources. The main functions of the operating system are:
• Process management: Sets up an environment in which multiple independent processes (programs) can run.
• Resource management: Controls access to all available resources, using schemes that may be based on priority or efficiency.
• I/O device management: Controls communication to all devices that are connected to the computer, including hard drives, printers, monitors, keyboard, mouse, and so on.
• Memory management: Controls the allocation and access to main memory (RAM), allocating it to processes, as well as general uses such as disk caching.
• File management: Controls the file systems that are present on hard drives and other types of devices and performs all file operations on behalf of individual processes.
• Communications management: Controls communications on all available communications media on behalf of processes.Process management: Sets up an environment in which multiple independent processes (programs) can run.
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