ch 4: hardware and software

What are the two important software constraints? Explain with suitable examples.

A particular version of an operating system is written for a particular type of hardware. For example, Microsoft Windows works only on processors from Intel and companies that make processors that conform to the Intel instruction set (the commands that a CPU can process). Furthermore, the 32-bit version of Windows runs only on Intel computers with 32-bit CPUs, and the 64-bit version of Windows runs only on Intel computers with 64-bit CPUs. Second, application programs are written to use a particular operating system. Microsoft Access, for example, will run only on the Windows operating system. Some applications come in multiple versions. There are, for example, Windows and Macintosh versions of Microsoft Word. But unless informed otherwise, it is safe to assume that a particular application runs on just one operating system.

________ is a type of computer software which is installed in special, read-only memory in devices like printers or communication devices. A) Firmware B) Instruction set C) Operating system D) Browser

A) Firmware

Which of the following is true of a 32-bit CPU? A) It cannot effectively utilize more than 4GB of main memory. B) It has a higher speed than any other processor. C) It is ideal for creating large, complicated spreadsheets. D) It is more expensive than the 64-bit CPU.

A) It cannot effectively utilize more than 4GB of main memory.

To execute an instruction, data is moved from the main memory to the CPU via the ________. A) bus B) operating system C) cache D) application

A) bus

Users employ ________ computers for word processing, spreadsheets, database access, and so forth. A) client B) cached C) licensed D) volatile

A) client

Which of the following patterns represents the value 11011? A) closed; closed; open; closed; closed B) open; closed; open; open; closed C) closed; open; open; open; closed D) open; closed; closed; open; open

A) closed; closed; open; closed; closed

CPU speed is expressed in ________. A) hertz B) bytes C) bits D) meters per second

A) hertz

Which of the following is considered to be input hardware? A) keyboard B) printers C) speakers D) screen projectors

A) keyboard

A ________ is 1,024 bytes. A) kilobyte B) megabyte C) gigabyte D) terabyte

A) kilobyte

21) Every computer has a(n) ________, which is a program that controls that computer's resources. A) operating system B) browser C) central processing unit D) instruction set

A) operating system

A grocery scanning checkout system is an example of ________. A) vertical-market software B) horizontal-market software C) a one-of- a-kind application D) an operating system

A) vertical-market software

Describe how computer data is sized.

All computer data are represented by bits. The data can be numbers, characters, currency amounts, photos, recordings, or whatever. All are simply a string of bits. Bits are grouped into 8-bit chunks called bytes. For character data, such as the letters in a person's name, one character will fit into one byte. Bytes are used to measure sizes of noncharacter data as well. For example, a given picture can be said to be 100,000 bytes in size. This statement means the length of the bit string that represents the picture is 100,000 bytes or 800,000 bits (because there are 8 bits per byte). The specifications for the size of main memory, disk, and other computer devices are expressed in bytes. A kilobyte, abbreviated K, is a collection of 1,024 bytes. A megabyte, or MB, is 1,024 kilobytes. A gigabyte, or GB, is 1,024 megabytes, a terabyte or TB, is 1,024 gigabytes, a petabyte, or PB, is 1,024 terabytes, and an exabyte, or EB, is 1,024 petabytes.

What are the different categories of application programs?

Application software consists of programs that perform a service or a function. Some application programs are general purpose. Other application programs provide specific functions. a. Horizontal-market application software provides capabilities common across all organizations and industries. Word processors, graphics programs, spreadsheets, and presentation programs are all horizontal-market application software. Examples of such software are Microsoft Word, Excel, and PowerPoint. b. Vertical-market application software serves the needs of a specific industry. Examples of such programs are those used by dental offices to schedule appointments and bill patients. Vertical applications usually can be altered or customized. c. One-of- a-kind application software is developed for a specific, unique need. The IRS develops such software, for example, because it has needs that no other organization has.

30) Which of the following is true of thick-client applications? A) A thick-client application is an application program that need not be preinstalled on the client. B) All other things being equal, thin-client applications are preferred over thick client applications. C) A thick-client application does not require preinstallation of client code. D) In large organizations which use thick-client applications, update installation and version management are inexpensive.

B) All other things being equal, thin-client applications are preferred over thick client applications.

Which of the following is true of in-house custom-developed software? A) They are less expensive than off-the- shelf software. B) The organization has to tailor its applications to the software. C) They are easy and comparatively cheap to make. D) Custom-developed software require no adaption even if needs change.

B) The organization has to tailor its applications to the software.

Which of the following is true of a client? A) They usually have multiple CPUs. B) They have software that enables them to connect to a network. C) They have limited video displays or no display at all. D) They can process emails or large shared databases.

B) They have software that enables them to connect to a network.

________ is the process whereby multiple operating systems share the same hardware. A) Machine coding B) Virtualization C) License sharing D) Cloud computing

B) Virtualization

Which of the following operating systems is most commonly used? A) Linux B) Windows C) Unix D) Mac OS

B) Windows

Which device listed below is an example of an output hardware device? A) keyboard B) flatbed plotter C) CPU D) magnetic disk

B) flatbed plotter

One ________ = 1024 kilobytes. A) terabyte B) megabyte C) gigabyte D) bit

B) megabyte

A(n) ________ is a program that controls the computer's resources. A) cache B) operating system C) CPU D) bus

B) operating system

7) One ________ is equivalent to 1024 gigabytes. A) petabyte B) terabyte C) megabyte D) kilobyte

B) terabyte

Memory is said to be ________ if contents are lost when power is off. A) cached B) volatile C) random D) swapped

B) volatile

Which of the following operating systems was developed by the open source community? A) Opera B) Windows C) Linux D) Mac OS

C) Linux

Which of the following is true of a server? A) Single but powerful CPUs are used by all servers. B) Extensive video displays characterize all servers. C) Processing shared databases is one of its functions. D) Servers cannot process emails and Web sites.

C) Processing shared databases is one of its functions.

________ is computer code as written by humans and that is understandable by humans. A) Open source B) Machine code C) Source code D) Native code

C) Source code

Software that provides capabilities common across all organizations and industries is known as ________ software. A) vertical-market application B) market-wide C) horizontal-market application D) generic-application

C) horizontal-market application

An individual buying a computer program ________. A) accrues liability for the usage of the program B) can install the program on multiple computers C) just buys a license to use the product D) can also use most other programs using the license

C) just buys a license to use the product

When there is not enough memory to load additional programs in the main memory, the operating system removes some programs/data and replaces it with the newly requested programs/data through a process called ________. A) data labeling B) force programming C) memory swapping D) data paging

C) memory swapping

20) For some commercial Web sites, the server is actually a large collection of computers, called a ________, that coordinates all of their activities. A) networking terminal B) workstation C) server farm D) data bus

C) server farm

24) Programs that control the server computer's resources are ________. A) client operating systems B) client application programs C) server operating systems D) server application programs

C) server operating systems

What are bits? Explain the various methods of representing binary notation.

Computers represent data using binary digits called bits. A bit is either a zero or a one. Bits are used for computer data because they are easy to represent physically and electronically. Binary notations are sometimes represented through switches. A switch can be either closed or open. A computer can be designed so that an open switch represents zero and a closed switch represents one. The orientation of a magnetic field is also used to represent a bit; magnetism in one direction represents a zero, magnetism in the opposite direction represents a one. Finally, for optical media, small pits are burned onto the surface of the disk so that they will reflect light. In a given spot, a reflection means a one; no reflection means a zero.

The CPU has a small amount of very fast memory called ________. A) the main memory B) a data channel C) a serial bus D) a cache

D) a cache

4) All computer data is represented by ________, irrespective of type. A) dots B) pixels C) tags D) bits

D) bits

Which of the following is part of volatile memory? A) magnetic disk B) magnetic tape C) optical disk D) cache

D) cache

Application programs that require programs other than a browser on a user's computer are called ________. A) thin-client applications B) horizontal applications C) vertical applications D) thick-client applications

D) thick-client applications

Differentiate between an operating system and an application program.

Every computer has an operating system, which is a program that controls that computer's resources. Some of the functions of an operating system are to read and write data, allocate main memory, perform memory swapping, start and stop programs, respond to error conditions, and facilitate backup and recovery. In addition, the operating system creates and manages the user interface, including the display, keyboard, mouse, and other devices. Although the operating system makes the computer usable, it does little application-specific work. To write a document or query a customer database, application programs such as Microsoft Word or Oracle's customer relationship management (CRM) software are needed. These programs must be licensed in addition to the operating system.

What is firmware?

Firmware is computer software that is installed into devices such as printers, print servers, and various types of communication devices. The software is coded just like other software, but it is installed into special, read-only memory of the printer or other device. In this way, the program becomes part of the device's memory; it is as if the program's logic is designed into the device's circuitry. Users do not need to load firmware into the device's memory. Firmware can be changed or upgraded, but this is normally a task for IS professionals. The task is easy, but it requires knowledge of special programs and techniques that most business users choose not to learn.

Describe the basic components of a generic computer.

In a generic computer, hardware consists of electronic components and related gadgetry that input, process, output, and store data according to instructions encoded in computer programs or software. Typical input hardware devices are the keyboard, mouse, document scanners, and bar-code scanners. Processing devices include the central processing unit (CPU), which is sometimes called the "brain"of the computer. The CPU works in conjunction with main memory. Main memory is sometimes called RAM, for random access memory. Computers also can have special function cards that can be added to the computer to augment the computer's basic capabilities. Output hardware consists of video displays, printers, audio speakers, overhead projectors, and other special-purpose devices. Storage hardware saves data and programs. The magnetic disk is by far the most common storage device, although optical disks such as CDs and DVDs also are popular.

What is unique about Linux as an operating system?

Linux is a version of Unix that was developed by the open source community. In case of Linux, no company can sell a license to use it. It is owned by the open source community, which states that Linux has no license fee (with certain reasonable restrictions). Large companies such as IBM, and smaller companies such as Red Hat can make money by supporting Linux, but no company makes money selling Linux licenses.

What are the drawbacks of developing custom application software for an organization?

Organizations develop custom application software themselves or hire a development vendor. By developing custom software, the organization can tailor its application to fit its requirements. Custom development is difficult and risky. Staffing and managing teams of software developers is challenging. Managing software projects can be daunting. Many organizations have embarked on application development projects only to find that the projects take twice as long—or longer—to finish as planned. For custom software developed in-house the developing company must pay all of the adaptation costs itself. Over time, this cost burden is heavy. Because of the risk and expense, in-house development is the last-choice alternative and is used only when there is no other option.

4) Briefly describe how a computer works.

The CPU (central processing unit) is the major actor. To run a program or process data, the computer must first transfer the program or data from disk to main memory. Then, to execute an instruction, it moves the instruction from main memory into the CPU via the data channel or bus. The CPU has a small amount of very fast memory called a cache. The CPU keeps frequently used instructions in the cache. Main memory of the computer contains program instructions for application programs and a browser. It also contains instructions for the operating system. Main memory is too small to hold all of the programs and data that a user may want to process. Consequently, the CPU loads programs into memory in chunks. If the user opens another program or needs to load more data, the operating system will direct the CPU to attempt to place the new program or data into unused memory. If there is not enough memory, it will remove something, and then it will place the just-requested program or data into the vacated space. This process is called memory swapping.

List the four major operating systems and their usages.

The four major operating systems are Windows, Mac OS, Unix, and Linux. a. For business users, the most important operating system is Microsoft Windows. Some version of Windows resides on more than 85 percent of the world's desktops, and considering just business users, the figure is more than 95 percent. Microsoft offers many different versions of Windows, the current version being Windows 8. b. Apple Computer, Inc., developed its own operating system for the Macintosh, Mac OS. The current system is named Mac OS X. Macintosh computers are used primarily by graphic artists and workers in the arts community. c. Unix is an operating system that was developed at Bell Labs in the 1970s. It has been the workhorse of the scientific and engineering communities since then. Unix is generally regarded as being more difficult to use than either Windows or the Macintosh. d. Linux is a version of Unix that was developed by the open source community. This community is a loosely coupled group of programmers who mostly volunteer their time to contribute code to develop and maintain Linux. The open source community owns Linux, and there is no fee to use it. Linux can run on client computers, but it is most frequently used on servers, particularly Web servers.

How does open source work? How is different from closed source projects?

The term open source means that the source code of the program is available to the public. Source code is computer code as written by humans and that is understandable by humans. Source code is compiled into machine code that is processed by a computer. Machine code is, in general, not understandable by humans and cannot be modified .In a closed source project, say Microsoft Office, the source code is highly protected and only available to trusted employees and carefully vetted contractors. The source code is protected like gold in a vault. Only those trusted programmers can make changes to a closed source project. With open source, anyone can obtain the source code from the open source project's Web site. Programmers alter or add to this code depending on their interests and goals. In most cases, programmers can incorporate code they find into their own projects. They may be able to resell those projects depending on the type of license agreement the project uses. Open source succeeds because of collaboration. A programmer examines the source code and identifies a need or project that seems interesting. He or she then creates a new feature, redesigns or reprograms an existing feature, or fixes a known problem. That code is then sent to others in the open source project who then evaluate the quality and merits of the work and add it to the product, if appropriate.

Differentiate between client and server computers.

Users employ client computers for word processing, spreadsheets, database access, and so forth. Most client computers also have software that enables them to connect to a network. Servers provide some service. Some servers process email; others process Web sites; others process large, shared databases; and some provide all of these functions or other similar functions. Server computers need to be faster, larger, and more powerful than client computers. They usually have multiple CPUs. Servers typically have limited video displays. Many servers have no display at all, because they are only accessed from another computer via the network. For large commerce sites, the server is actually a large collection of computers (called a server farm) that coordinate all of their activities.

What is virtualization?

Virtualization is the process by which one computer hosts the appearance of many computers. For example, with virtualization one server can support two instances of Windows Server, one instance of Linux, and three instances of Windows. Because these instances are isolated, it will appear to each that it has exclusive control over the server computer. Because of virtualization, it is quite easy for cloud vendors to reconfigure servers to support changes in workload.

How can individuals and firms buy computer programs?

When one buys a computer program, it does not mean actually buying that program. Instead, one is buying a license, which is the right to use a certain number of copies of that program subject to limits on the vendor's liability. Large organizations do not buy a license for each computer user. Instead, they negotiate a site license, which is a flat fee payment for the right to install the product (operating system or application) on all of that company's computers or on all of the computers at a specific site.

order of byts

kilo = 1024 bytes mega = 1024 kilos giga = 1024 megas tera = 1024 gigas reta = 1024 teras exa = 1024 retas zetta = 1024 exas