Review Chapter:  Microcomputer Operating Systems - Hardware, Software, and the Operating System FAQ's

1. Define hardware
The hardware consists of the physical components of the computer. If you can pick it up or look at it then it is hardware. Examples of hardware are monitors, keyboards, system units, and mouse. Hardware by itself can do little; software tells the hardware what to do.

2. Define software
Computer software is made up of sets of very detailed instructions that the computer uses to do its work. Software is what makes a computer work. It is loaded into memory and allows you to create and manipulate data and /or perform a task. In other words you tell software what to do, then software tells hardware what to do.

3. What is data?
In a computer sense, the numbers, letters and text and other information used by the software to give the answers wanted by the user.

4. What is meant by the system configuration?
Microcomputers are comprised of hardware components. The system configuration is the basic components (hardware) of a complete system on a specific microcomputer. These include the type of processor, number and types of disk drives, type of monitor, amount of memory, printers, mouse, modem, and other peripherals.

5. Describe a typical microcomputer configuration.
A typical microcomputer configuration includes an input device (typically a keyboard), a system unit that contains the CPU, adapter cards, ROM and RAM, a display unit (typically a monitor), and some type of external storage medium (such as disk drives), and usually includes a printer. Today a typical system configuration will also include some kind of pointing device such as a mouse or trackball and will often include a CD-ROM, as well as a sound card for multi-media.

6. What is the purpose and function of the bus?
The bus is the electrical connections between the CPU and all other devices. It is the means by which the CPU can deliver information to all of the devices.

7. Compare and contrast RAM, Cache, and ROM.
RAM (Random Access Memory) is the workplace of the computer that is often referred to as memory or conventional memory. It is the place where programs and data are placed while the computer is working. RAM is volatile (temporary) which means that all data placed in RAM (unless saved) is lost when the computer is turned off.

ROM (Read-Only Memory) contains the most basic instructions for the computer. It is a chip with programs written on it and was designed to hold permanently stored programs installed by the computer manufacturer. ROM usually holds start-up routines of the computer. It is non-volatile which means that none of information stored on ROM is lost when the computer is turned off. It is considered to be firmware because it is both hardware (a chip) and software (it contains information).

Cache stores frequently used RAM data. Its purpose to speed up the process of data access. Cache memory is expensive memory and is used sparingly.

8. Explain firmware.
Firmware is a cross between software (instructions) and hardware. It is software that has been permanently programmed onto ROM chips and then the chip is permanently installed in the computer. It has read-only programs on it which are responsible for the system tests and looking for the boot record on the system disk. Firmware acts as the interface between the hardware and the operating system.

9. What is an adapter board?
An adapter board is a printed circuit board that is placed in an expansion slot in the computer. It is installed in a computer to allow the installation and control of some type of device, such as a monitor.

10. List two input and two output devices and briefly explain how these devices work.
All input devices take user input and translate it into a form that the computer can understand and use. The two most common input devices are the keyboard and the mouse or trackball.

All output devices take computer data and translate it into a form that the user can use. The most common output devices are the monitor and the printer (hard copy).

Neither input nor output devices do any significant processing of the data. For example if you press a key on the keyboard the processing is limited to getting the value of that key to the CPU.

11. What purpose do disks serve?
Disks are media that allow permanent storage of programs and data even when the computer is turned off. If data is stored on floppy disks it makes it possible to move data and/or programs from one computer to another.

12. What is the difference between disk storage and memory capacity?
Memory is the immediate workplace of the computer. In order for a program to run, or for data to be used, it must be loaded into memory. How much memory is available on a computer is the memory capacity of the computer. It is important to know the memory capacity of your computer to determine how big a program and/or data your computer can hold. All information that is placed in memory (unless saved) is lost when the computer is turned off. You might think of memory capacity as the size of your desk or working area.

Disk storage is long term storage. This is where data and programs are kept until they are needed on the workspace. You might think of disk storage as filing cabinets. It is not relevant if disk storage is on a floppy disk or hard disk - the hard disk simply increases the amount of information you can store.

13. What is a CD-ROM?
CD-ROM's are devices used to read information from compact disks. These disks, identical to music CD's, can hold hundreds of megabytes of information. Currently they can only be read from and never written to. As programs grow larger, these CD-ROM's will provide a lot of storage in a removable media at a low cost. It is expected that in the near future CD-ROM's will also be able to be written to.

14. What is the difference between a hard disk and a floppy disk?
Hard disks are much faster and much larger than floppy disks. Floppy disks are portable whereas hard disks are usually not.

Floppy disks are usually used for moving data from computer to computer and making backup copies of information while hard disks are used for primary storage.

15. What are tracks and sectors? Where are they found?
Both tracks and sectors are found on disks. Disks are divided into concentric circles called tracks. Each track is then further divided into sectors. This is true of all hard and floppy disks. The number of tracks and sectors depends on the format of the disk. Both the tracks and sectors are used to help organize data on the disk.

16. What is a cluster? What is it comprised of?
A cluster is the basic unit of disk storage. It is the smallest logical unit which can be addressed on a disk by the operating system. A cluster is made up of one or more adjacent sectors, depending upon the size of the disk.

17. What is a device?
A device is some piece of hardware that is attached to the computer (usually by external cables). Each device has a reserved, unique name assigned to it. Typically devices are written to or read from for input/output. Common devices include keyboards, monitors, printers, and disk drives. The first floppy drive is referred to by the device name of A:

18. Compare and contrast application software with system software.
System software is the interface between the hardware and application software. System software coordinates the operation of the hardware. It is mandatory for running application software. System software is computer oriented.

Application software is the software is what actually does some task. Typically application software is designed to solve some problem such as entertainment, billing, or writing. The application software solves problems, handles information, and is user-oriented. The data is handled only by the application software.

19. Can application packages run without an operating system? Why or why not?
Application packages need an operating system to run. The operating system acts as the interface between the application software and the computer itself. Without the operating system, the application will not run.

20. Define OS.
OS (Operating System) is the system software that coordinates the operation of all the system hardware and supervises the processing of application programs. It is the interface between the application software and the hardware as well as the user and the computer. An operating system is loaded into memory when the computer is booted. It must be loaded prior to any application software.

21. Where is OS stored for use by the computer?
The OS system files are stored on disk. In order to be used the OS must be loaded into memory. Internal commands are kept in memory (RAM) during the time the computer is on after the operating system is booted. External commands or utility programs are stored on disk and are loaded into memory only when requested. Utility programs are not mandatory to use an operating system.

22. Define BIOS.
BIOS (Basic Input/Output System) keeps track of the computer's hardware. The BIOS works with the operating system and application software to manage use of hardware. It provides the interface between the hardware and OS.

23. What is the function of an operating system?
An operating system acts as the interface between the computer hardware and the application software. It provides all the services needed by users and applications for handling disks and files.

24. Compare and contrast internal and external commands.
An internal command is always present in the computer. It is stored in RAM and is therefore resident in memory. It is always available to use, so the OS does not need to go to a disk to find and load the program. It is loaded with the operating system and remains in memory until the power is turned off.

An external command does not permanently reside in RAM. It is stored on a disk and must be loaded into memory each time it is used. An external command is transient and does not remain in memory after it is executed. Both OS utility programs and application software are external commands.

25. What is the purpose and function of a network?
Networks are two or more computers connected together that can share programs and files and usually share peripheral devices such as printers. They allow for easier administration and maintenance and usually allow the saving of money as fewer printers and/or hard drives are required.

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Sujan Sarkar - CIS Instructor, Santa Rosa Junior College
Updated Monday January 17, 2011