CH.2 computers and their business applications
project management software (application software)
A project, such as designing a Web site or setting up an order entry system, consists of a set of related tasks. - The goal of project management software is to help project managers keep time and budget under control by solving scheduling problems, planning and setting goals, and highlighting potential bottlenecks. - ex. Wrike, Smartsheet, and Clarizen
spreadsheet software (application software)
A spreadsheet is a table of rows and columns, and spreadsheet software is capable of performing numerous tasks with the information in a spreadsheet - ex. Microsoft Excel, IBM's Lotus 1-2-3, and Corel Quattro Pro.
4th gen computer language
Fourth-generation language
advantages for cloud storage
Access your files anytime, anywhere Prevent data loss Reduced cost Improved collaboration Improved security No maintenance
3rd gen computer language
High-level language
1st gen computer language
Machine language
5th gen computer language
Natural language processing (NLP)
classes of computers
Subnotebooks, notebooks, personal, minicomputers, mainframes, supercomputers - Supercomputers are the most powerful; they also have the highest storage capabilities and the highest price. - Mainframe computers are usually compatible with the IBM System/360 line introduced in 1965. As mentioned in the Industry Connection later in this module, IBM System zEnterprise EC12 is the latest example in this class. Systems that are not based on System/360 are referred to as "servers" or supercomputers.
garbage in, garbage out (GIGO)
The concept that the quality of the output is only as good as the quality of the input. - If data is erroneous, the information the computer provides is also erroneous
cloud storage
Used for online storage and backup, cloud storage involves multiple virtual servers that are usually hosted by third parties. Customers buy or lease storage space from third parties based on their current or future needs. - Dropbox, OneDrive, and Google Drive - may reduce the demand for some of the traditional storage devices or even replace some of them
storage area network (SAN)
a dedicated high-speed network consisting of both hardware and software used to connect and manage shared storage devices, such as disk arrays, tape libraries, and optical storage devices. - makes storage devices available to all servers on a local area network (LAN) or wide area network (WAN) - is a dedicated network, servers can access storage devices more quickly and do not have to use their processing power to connect to these devices - are used only in large enterprises because of their cost and installation complexity. - speed up data access performance and, despite their cost, they are more economical than having storage devices attached to each server - easy capacity extensibility
bus
a link between devices connected to the computer. It can be parallel or serial, internal (local) or external. - interal: enables communication between internal components, such as a video card and memory - external: capable of communicating with external components, such as a USB device
computer
a machine that accepts data as input, processes data without human intervention by using stored instructions, and outputs information. - only processes data, can't change or correct data that is entered
disk drive
a peripheral device for recording, storing, and retrieving information.
most common type of main memory
a semiconductor memory chip made of silicon - semiconductor memory device can be volatile or nonvolatile
cloud printing
a service that allows users to print from any device on the network and implement the print-on-demand strategy. - connects devices on the network such as smartphones, tablets, laptops, and workstations with printer stations. Users could print remotely from their personal devices. - Users could print remotely from their personal devices - advantages include reduced cost and convenience. Users no longer have to worry about software, drivers, or cables as it eliminates compatibility issues
operating system (OS)
a set of programs for controlling and managing computer hardware and software. It provides an interface between a computer and the user and increases computer efficiency by helping users share computer resources and by performing repetitive tasks for users. - typical OS consists of control programs and supervisor programs - time shared versions allow several users to use computer resources simultaneously. - computer versions: Microsoft Windows, Mac OS, and Linux - mainframe versions: UNIX and OpenVMS as well as some versions of Linux.
software
all the programs that run a computer system - two types: 1. system 2. application
remote access server (RAS)
allow off-site users to connect to network resources, such as network file storage, printers, and databases.
supervisor programs (part of an OS)
also known as the kernel - is responsible for controlling all other programs in the OS, such as compilers, interpreters, assemblers, and utilities for performing special tasks
parallel port
an interface between a computer and a printer that enables the computer to transfer multiple bits of information to the printer simultaneously
object (OOP)
an item that contains both data and the procedures that read and manipulate it. - ex. a person, an event, or a transaction
barcode reader (input)
an optical scanner that uses lasers to read codes in bar form. These devices are fast and accurate and have many applications in inventory, data entry, and tracking systems. They are used mostly with UPC systems in retail stores.
mail server
are configured for sending, receiving, and storing e-mail.
high level languages (3rd gen)
are machine independent and part of the third generation of computer languages. - Many languages are available, and each is designed for a specific purpose. - ex. C++, Java, and VB.NET - languages are used mostly for Web development and Internet applications - are more like English, so they are easier to learn and code. - In addition, they are self-documenting, meaning that you can usually understand the programs without needing additional documentation
3 basic tasks a computer can perform
arithmetic operations logical operations storage and retrieval operations - All other tasks are performed using one or a combination of these operations
application software
computer software created to allow the user to perform a specific job or task - is used to perform specialized tasks - ex. Microsoft Excel for spreadsheet analyses and number-crunching tasks - can be commercial software or software developed in-house and is used to perform a variety of tasks on a personal computer. - In-house software is usually more expensive than commercial software but is more customized and often fits users' needs better.
4th gen computers 1971-1992
computers continued several trends that further improved speed and ease of use: miniaturization, very-large-scale integration (VLSI) circuits, widespread use of personal computers, and optical discs (discs written or encoded and read using a laser optical device). - ex. Cray XMP, Cray II
5th gen computers (current gen) 1993-present
computers include parallel processing (computers containing hundreds or thousands of CPUs for rapid data processing), gallium arsenide chips that run at higher speeds and consume less power than silicon chips, and optical technologies - gallium-arsenide chips have electrons move almost five times faster than silicon. - gallium-arsenide chips can emit light, withstand higher temperatures, and survive much higher doses of radiation than silicon devices - gallium-arsenide chips difficult to mass produce - optical tech involves the applications and properties of light, including its interactions with lasers, fiber optics, telescopes, and so forth. These technologies offer faster processing speed, parallelism (several thousand light beams can pass through an ordinary device), and interconnection; much denser arrays of interconnections are possible because light rays do not affect each other. - ex. IBM System zEnterprise EC12
3rd gen computers 1964-1970
computers operated on integrated circuits, which enabled computers to be even smaller, faster, more reliable, and more sophisticated. - Remote data entry and telecommunications were introduced during this generation. - ex. IBM 360, 370
2nd gen computers 1957-1963
computers used transistors and were faster, more reliable, and easier to program and maintain. - ex. IBM 7094, 1401
1st gen computers 1946-1956
computers used vacuum tube technology. They were bulky and unreliable, generated excessive heat, and were difficult to program. - ex. ENIAC
binary system
consists of 0s and 1s, with a 1 representing "on" and a 0 representing "off," similar to a light switch.
data tablet (input)
consists of a small pad and a pen - Menus are displayed on the tablet, and you make selections with the pen - used most widely in computer-aided design and manufacturing applications.
software components of a computer
consists of programs written in computer languages.
disk server
contain large-capacity hard drives and enable users to store files and applications for later retrieval.
file server
contain large-capacity hard drives for storing and retrieving data files.
fax server
contain software and hardware components that enable users to send and receive faxes.
how computers are primarily classified
cost, amount of memory, speed, and sophistication
unicode
data code capable of representing 256 (2^8) characters
print server
enable users to send print jobs to network printers.
inheritance (principle of OOP)
enables new objects to take on the properties of existing objects. - This feature reduces application development time by using existing codes
dual-core processor
essentially two processors in one - common in new PCs and Apple computers
machine language (1st gen)
first generation of computer languages - consists of a series of 0s and 1s representing data or instructions. - It is dependent on the machine, so code written for one type of computer does not work on another type of computer.
voice synthesis
for converting computer output to voice - Cash registers at grocery stores use it to repeat item prices - When you call directory assistance, the voice you hear is probably computer generated. - is utilized by digital assistants such as Amazon's Alexa and Google's Home.
3 major computer components needed to use a computer and process data
input devices output devices memory devices
CPU case
is also known as a computer chassis or tower. It is the enclosure containing the computer's main components.
Network-attached storage (NAS)
is essentially a network-connected computer dedicated to providing file-based data storage services to other network devices. - software on this handles features such as data storage, file access, and file and storage management. - is popular for Web servers and e-mail servers because it lowers management costs and helps make these servers more fault-tolerant. It is also becoming a useful solution for providing large amounts of heterogeneous data (text, documents, voice, images, movies, etc.) for consumer applications. - biggest issue is that as the number of users increases, its performance deteriorates - can be easily expanded
Magnetic tape
is made of a plastic material and stores data sequentially. - Records can be stored in a block or separately, with a gap between each record or block, called the interrecord gap (IRG) - is sometimes used for storing backups
computer speed measurements
is measured as the number of instructions performed during the following fractions of a second: Millisecond: 1/1,000 of a second Microsecond: 1/1,000,000 of a second Nanosecond: 1/1,000,000,000 of a second Picosecond: 1/1,000,000,000,000 of a second
Financial Planning and Accounting Software (application software)
is more powerful than spreadsheet software, is capable of performing many types of analysis on large amounts of data. - These analyses include present value, future value, rate of return, cash flow, depreciation, retirement planning, and budgeting. - A widely used financial planning package is Intuit Quicken - dedicated accounting software is available for performing many sophisticated accounting tasks, such as general ledgers, accounts receivable, accounts payable, payroll, balance sheets, and income statements. - Some popular accounting software packages include Quickbooks, Xero, and Zoho Books.
secondary memory
is nonvolatile, holds data when the computer is off or during the course of a program's operation. It also serves as archival storage. - used for storing large volumes of data for long periods - There are three main types: magnetic disks, magnetic tape, and optical discs - include hard disks, USB flash drives, and memory cards.
read-only memory (ROM)
is nonvolatile; data cannot be written to it - type of data usually stored here includes BIOS information and the computer system's clock
Optical mark recognition (OMR) system (input)
is sometimes called a "mark sensing" system because it reads marks on paper - often used to grade multiple-choice and true/false tests.
microphone (input)
is used as an input device to input sound to a computer, which will be stored in a digital format. - Sound could be added to a multimedia presentation or used for generating music or an advertising piece.
presentation software (application software)
is used to create and deliver slide shows. - Microsoft PowerPoint is the most commonly used - can include many types of content in slide shows, such as bulleted and numbered lists, charts, and graphs. You can also embed graphics as well as sound and movie clips. - also offers several options for running slide shows, such as altering the time interval between slides. In addition, you can usually convert presentations into other formats, including Web pages and photo albums with music and narration
abstraction (OOP principle)
is used to handle complexity by hiding unnecessary details from the user. - This principle looks at a problem from a higher level and then gets into detail in later stages of code development
desktop publishing software (application software)
is used to produce professional-quality documents without expensive hardware and software. This software works on a "what-you-see-is-what-you-get" (WYSIWYG, pronounced "wizzy-wig") concept, so the high-quality screen display gives you a good idea of what you will see in the printed output. - used for creating newsletters, brochures, training manuals, transparencies, posters, and even books. - ex. Xara Page & Layout Designer, Adobe InDesign, and Microsoft Office Publisher.
random access memory (RAM)
is volatile memory, in which data can be read from and written to; it is also called read-write memory. - In other words, data can be read from and written to it
trackball (input)
kept in a stationary location, but it can be rolled on its axis to control the on-screen cursor. - occupy less space than a mouse, so they are ideal for notebook computers, but can be less accurate than mice
object-oriented programming (OOP)
language is organized around a system of objects that represent the real world as opposed to a series of computational steps used in traditional languages. - ex. Java, Ruby, Swift, C#, and Visual Basic - Simplicity and adaptability are among the key features - 2 main parts: - objects - classes - Abstraction, inheritance, polymorphism, and encapsulation are four key principles - each one is tailored to a specific OS and programming environment - ex. Swift is mostly used for programming environment and apps development for MacOS and iOS; C#, developed by Microsoft, is mostly used for Windows apps and Windows programming environment; and Java is used for cross-platform development
magnetic disk
made of Mylar or metal, is used for random-access processing. In other words, data can be accessed in any order, regardless of its order on the surface. - type of secondary memory - are much faster but more expensive than tape devices.
Two types of memory
main and secondary
digital camera (input)
may serve as both an input and output device by having the user take a picture then send the picture to a computer or another device for display
retrieval capabilities
means accessing data from memory
encapsulation (principle of OOP)
means grouping related items into a single unit. This helps handle more complex types of data, such as images and graphs.
storage capabilities
means saving data in computer memory - data is stored in bits. - A bit is a single value of 0 or 1, and 8 bits equal 1 byte. - A byte is the size of a character
hard copy output
most common device for this output is a printer
arithmetic logic unit (ALU)
performs arithmetic operations (+, −, ∗, /) as well as comparison or relational operations (<, >, =); the latter are used to compare - 1 part of the CPU
computer hardware components
physical devices, such as keyboards, monitors, and processing units
mouse (input)
pointing device moves the cursor on the screen, allowing fast, precise cursor positioning. - input of choice for GUIs
inkjet printer
printers that produce characters by projecting onto paper electrically charged droplets of ink that create an image - high quality ones use multicolor ink cartridges for near-photo quality output and are often used to print digital photographs. - are suitable for home users who have limited text and photo printing needs
laser printers
printers that use laser-based technology that creates electrical charges on a rotating drum to attract toner. - toner is fused to paper using a heat process that creates high-quality output. - better suited to larger office environments with high-volume and high-quality printing requirements.
32-bit processor
processor that can use 2^32 bytes (4 GB) of RAM
64-bit processor
processor that can use 2^64 bytes (16 EB, or exabytes) of RAM
control programs (part of an OS)
programs manage computer hardware and resources by performing the following functions: - Job management—Control and prioritize tasks performed by the CPU. - Resource allocation—Manage computer resources, such as storage and memory. In a network, programs are also used for tasks, such as assigning a print job to a particular printer. - Data management—Control data integrity by generating checksums to verify that data has not been corrupted or changed. When the OS writes data to storage, it generates a value (the checksum) along with the data. The next time this data is retrieved, the checksum is recalculated and compared with the original checksum. If they match, the integrity is intact. If they do not, the data has been corrupted somehow. - Communication—Control the transfer of data among parts of a computer system, such as communication between the CPU and I/O devices.
Magnetic ink character recognition (MICR) system (input)
reads characters printed with magnetic ink and is used primarily by banks for reading the information at the bottom of checks.
cache RAM
resides on the processor. Because memory access from main RAM storage takes several clock cycles (a few nanoseconds), this type of RAM stores recently accessed memory so the processor is not waiting for the memory transfer.
system software
software responsible for the general operation of a computer system, including the operation of hardware, running application software, and file management - ex. Windows - the OS for most PCs - This type of software works in the background and takes care of housekeeping tasks, such as deleting files that are no longer needed.
word processing software (application software)
software used to generate documents. Typically, this includes editing features, such as deleting, inserting, and copying text. - advanced software often includes sophisticated graphics and data management features. - saves time, especially for repetitive tasks - ex. Microsoft Word, Corel WordPerfect, and OpenOffice.
3 things computer draw their power from:
speed accuracy storage and retrieval capabilities
program
step-by-step directions for performing a specific task, written in a language the computer can understand - instructions for a computer
web server
store Web pages for access over the Internet.
database server
store and manage vast amounts of data for access from users' computers.
application server
store computer software, which users can access from their workstations
Main Memory (RAM)
stores data and information and is usually volatile; its contents are lost when electrical power is turned off. It plays a major role in a computer's performance. - to some extent, the more memory a computer has, the faster and more efficient its input/output (I/O) operations are
input devices
such as keyboards, are used to send data and information to the computer
output devices
such as monitors and printers, display the output a computer generates. - capable of representing information from a computer - form may be visual, audio, or digital; examples include printers, display monitors, and plotters.
redundant array of independent disks (RAID)
system is a collection of disk drives used for fault tolerance and improved performance and is typically found in large network systems. - Data can be stored in multiple places to improve the system's reliability - sequences of data can be read from multiple disks simultaneously, which improves performance.
control unit
tells the computer what to do, such as instructing the computer which device to read or send output to. - 1 part of the CPU
most common data code for text files, PC applications, and the Internet
the American Standard Code for Information Interchange (ASCII) - developed by the American National Standards Institute - in a file, each alphabetic, numeric, or special character is represented with a 7-bit binary number (a string of 0s or 1s). Up to 128 (2^7) characters can be defined - extended version allows rep of 256 characters
polymorphism (principle of OOP)
the ability to process objects differently depending on their data type or class. - As an example, this technique enables a programmer to define different shapes such as circles, rectangles, and triangles from a base class shape.
Central Processing Unit (CPU)
the heart of a computer. It is divided into two components: the arithmetic logic unit (ALU) and the control unit.
motherboard
the main circuit board containing connectors for attaching additional boards. It usually contains the CPU, basic input/output system (BIOS), memory, storage, interfaces, serial and parallel ports, expansion slots, and all the controllers for standard peripheral devices, such as the display monitor, disk drive, and keyboard.
keyboard (input)
the most widely used input device - designed to resemble typewriters, but several modifications have been made to improve their ease of use - include control keys, arrow keys, function keys, and other special keys - can perform most computer input tasks
assembly language (2nd gen)
the second generation of computer languages, is a higher-level language than machine language but is also machine dependent. - It uses a series of short codes, or mnemonics, to represent data or instructions. - ex. ADD and SUBTRACT are typical commands - easier to write programs than machine language
Multiprocessing
the use of two or more CPUs in a single computer system.
(T/F) A SAN offers only storage; a NAS system offers both storage and file services.
true
(T/F) a program is also referred to as source code
true
(T/F) silicon chips cannot emit light and have speed limitations
true
(T/F) source code must be translated into object code—consisting of binary 0s and 1s. Binary code—a set of instructions used to control the computer—uses 0s and 1s, which the computer understands as on or off signals.
true
Fourth-generation languages (4GLs)
use macro codes that can take the place of several lines of programming. - The commands are powerful and easy to learn, even for people with little computer training. - are the easiest computer languages to use - are called nonprocedural languages, which means you do not need to follow a rigorous command syntax to use them. - instead, use macro codes that can take the place of several lines of programming. - ex. SQL
Fifth-generation languages (5GLs)
use some of the artificial intelligence technologies, such as knowledge-based systems, natural language processing (NLP), visual programming, and a graphical approach to programming. - These languages are designed to facilitate natural conversations between you and the computer. - Codes are automatically generated and designed to make the computer solve a given problem without a programmer or with minimum programming effort - ex. ActiveX, C++, Java, JavaScript, Perl, Python, PHP, Visual Basic, and Extensible Stylesheet Language (XSL), Web development languages are Hypertext Markup Language (HTML) and eXtensible Markup Language (XML). - Both languages are markup languages, not full-featured programming languages.
main (primary) memory
where computers store data and instructions, similar to a human brain
optical character reader (OCR) (input)
works on the same principle as a barcode reader but reads text instead. - must be able to recognize many special characters and distinguish between uppercase and lowercase letters, so using one is more difficult than using a barcode reader
class (OOP)
defines the format of the object and the action that it performs. - ex. an automobile (contains several makes and models)
database software (application software)
designed to perform operations such as creating, deleting, modifying, searching, sorting, and joining data. - A database is essentially a collection of tables consisting of rows and columns. - makes accessing and working with data faster and more efficient - ex. Microsoft Access, FileMaker Pro, and Alpha Software's Alpha Five - enterprise ex. Oracle, IBM DB2, and Microsoft SQL Server.
graphics software (application software)
designed to present data in a graphical format, such as line graphs and pie charts. - These formats are useful for illustrating trends and patterns in data and for showing correlations. - Graphics are created with integrated packages, such as Excel, Lotus 1-2-3, and Quattro Pro, or dedicated graphics packages, such as Adobe Photoshop
Current trends in input/output devices may be summarized as
Thinner and lighter laptops and tablets Faster and larger memory Widespread applications of wireless devices Increased applications of interactive computing using gesture, touch, and voice
storage approximations
1 bit: A single value of 0 or 1 8 bits: 1 byte or character 2^20 bytes: 1,000,000 bytes, or 1 megabyte (MB) 2^30 bytes: 1,000,000,000 bytes, or 1 gigabyte (GB) 2^40 bytes: 1,000,000,000,000 bytes, or 1 terabyte (TB) 2^60 bytes: 1,000,000,000,000,000,000 bytes, or 1 exabyte (EB)
computer aided design software (CAD) (application software)
(CAD) software is used for drafting and design and has replaced traditional tools, such as T-squares, triangles, paper, and pencils. - It is used extensively in architecture and engineering firms, but because of major price reductions and increases in PC power, small companies and home users can now afford this software. - ex. AutoCAD, Rhino3D, and DesignSpar
major advantages of OOP
- Modularity: Codes are written for specific and self-contained modules. This makes it easier to write codes, modify them, and troubleshoot them easier than traditional codes. New features can easily be added as new modules without any impact on existing modules. - Reuse of codes for other purposes: Codes written for one object can be simply modified by maintaining its major parts and applying it to another object. - Effective problem solving: OOP languages allow the programmer to break down a program into small-sized problems that a programmer can solve one module or one object at a time.
2nd gen computer language
Assembly language
soft copy output
Output displayed on a screen - most common devices are cathode ray tube (CRT), plasma display, and liquid crystal display (LCD). - Soon, the organic light-emitting diode (OLED) display will replace LCD
touch screen (input)
a combination of input devices, usually working with menus - some use light detection, others are pressure sensitive
serial port
a communication interface through which information is transferred one bit at a time
server
a computer and all the software for managing network resources and offering services to a network.
