Transcript Introduction to Information Technology: Your Digital World

Introduction to Information Technology: Your Digital World
Using Information Technology, 10e
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© 2013 The McGraw-Hill Companies, Inc. All rights reserved.
Introduction to Information Technology: Your Digital World
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Using Information Technology, 10e
© 2013 The McGraw-Hill Companies, Inc. All rights reserved.
Introduction to Information Technology: Your Digital World
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Using Information Technology, 10e
© 2013 The McGraw-Hill Companies, Inc. All rights reserved.
Introduction to Information Technology: Your Digital World
• A database is a logically organized collection of
related data designed and built for a specific purpose
• File (table): collection of related records
• Records (row): collections of related fields
• Field (column): unit of data containing 1 or more
characters
• Character [Byte]: a letter number or special character
made of bits
• Bit: 0 or 1
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Introduction to Information Technology: Your Digital World
• Key Field (primary key) – the field that uniquely
identifies a record
• Often an identifying number, such as social security
number or a student ID number
• Keys are used to sort records in different ways
• Primary keys must be unique make records
distinguishable from one another
• Foreign keys appear in other tables and usually refer
to primary keys in particular tables; they are used to
relate one table to another (to cross-reference data)
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Using Information Technology, 10e
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Introduction to Information Technology: Your Digital World
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Using Information Technology, 10e
© 2013 The McGraw-Hill Companies, Inc. All rights reserved.
Introduction to Information Technology: Your Digital World
• Database Management System (DBMS)
• Software written specifically to control the structure of a
database and access to the data
• DBMS benefits:
1.
2.
3.
4.
5.
Reduced data redundancy (redundant data is stored in
multiple places, which causes problems keeping all the
copies current)
Speed—Modern DBMSs are much faster than manual
data-organization systems
Improved data integrity—The data is accurate, consistent,
and up to date
Timeliness—The data can be supplied in a timely fashion—
when people need it.
Ease of sharing—The data in a database is usually shared
over a network by an entire organization.
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Introduction to Information Technology: Your Digital World
6. Ease of data maintenance—DBMS offers backup utilities, and
standard procedures for data inserting, updating, and
deletion.
7. Forecasting capabilities—DBMSs can hold massive amounts of
data that can be studied, and compared in order to forecast
behaviors in markets and to support the decision making
process.
8. Increased security—Although various departments may share
data, access to specific information can be limited to selected
users—called authorization control.
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Introduction to Information Technology: Your Digital World
• 3 Principal Database Components
• Data Dictionary
• Repository that stores the data definitions and descriptions
of the structure of the data and the database
• DBMS Utilities
• Programs that allow you to maintain the database by
creating, editing, deleting data, records, and files
• Report Generator
• Program for producing on-screen or printed readable
documents from all or part of a database
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Using Information Technology, 10e
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Introduction to Information Technology: Your Digital World
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Using Information Technology, 10e
© 2013 The McGraw-Hill Companies, Inc. All rights reserved.
Introduction to Information Technology: Your Digital World
1. Hierarchical Database
•
Fields or records are arranged in related groups
resembling a family tree with child (low-level)
records subordinate to parent (high-level) records
2. Network Database
•
Similar to a hierarchical database but more flexible- each child record can have more than one parent
record
3. Object-Oriented Database
• An object consists of:
• Data in any form, including audio, graphics, and video
• Instructions on the action to be taken with the data
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Introduction to Information Technology: Your Digital World
4. Relational Database
• Data stored in tables (relations, or files) of rows
(tuples, or records) and columns (attributes, or
fields)
• More flexible than previous models; built with SQL
• Example for large systems is Oracle
• Example for microcomputers is Microsoft Access
• Users employ SQL (structured query language) to
create, modify, maintain, and query the database
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Using Information Technology, 10e
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Introduction to Information Technology: Your Digital World
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Using Information Technology, 10e
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Introduction to Information Technology: Your Digital World
• Data mining is the computer-assisted process of sifting
through and analyzing vast amounts of data to extract
hidden patterns and meaning and to discover new
knowledge
• Data and meta-data (data about the data) are transported
to a data warehouse after some data fusion and data
cleansing processes
• Data warehouse is a special database of cleaned-up data
and meta-data
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Introduction to Information Technology: Your Digital World
Data Mining
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Using Information Technology, 10e
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Introduction to Information Technology: Your Digital World
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Using Information Technology, 10e
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Introduction to Information Technology: Your Digital World
• E-Commerce (Electronic Commerce)
• The buying and selling of products and services
through computer networks
• Examples of some e-tailers (electronic retailers):
• amazon.com sells books and almost everything else
• priceline.com sells airline tickets and hotel rooms
• dell.com sells computers and other electronic items
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Using Information Technology, 10e
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Introduction to Information Technology: Your Digital World
• Innovative e-tailer technologies make online
shopping easier
• 360-degree images
• Allow you to see all sides of an item
• Order tracking
• Codes are assigned to items being shipped that allow
customers to track shipping progress via the internet
• Shop bots
• Programs that help users search for a particular product or
service and then provide price comparisons
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Introduction to Information Technology: Your Digital World
• Types of E-Commerce
• Business-to-Business (B2B)
• A business sells to other businesses using the internet or a
private network
• Business-to-Consumer (B2C)
• A business sells goods or services directly to consumers
• Consumer-to-Consumer (C2C)
• Consumers sell goods or services directly to other
consumers with the help of a third party, such as eBay
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Introduction to Information Technology: Your Digital World
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Using Information Technology, 10e
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Introduction to Information Technology: Your Digital World
• AI is a group of related technologies used to develop
software and machines that emulate human qualities
such as learning, reasoning, communicating, seeing, and
hearing
• Areas include:
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•
•
•
Expert systems
Natural language processing
Pattern recognition
Robotics
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Introduction to Information Technology: Your Digital World
• Expert Systems
• Also called knowledge-based system
• Three components of an expert system:
• Knowledge base: an expert system’s database of
knowledge about a particular subject
• Inference engine: the software that controls the search of
the expert system’s knowledge base and produces
conclusions
• User interface: the display screen for the user to interact
with the expert system
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Introduction to Information Technology: Your Digital World
Expert System
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Using Information Technology, 10e
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Introduction to Information Technology: Your Digital World
• Natural language processing
• Allows users to interact with a system using normal
language
• The study of ways for computers to recognize and
understand human language
• Pattern recognition
• Involves a camera and software that identify visual
patterns by mapping them against similar patterns
stored in a database
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Introduction to Information Technology: Your Digital World
• Robotics
• The development and study of machines that can
perform work that is normally done by people
• Commonly found in factories and also in situations
where people would be in danger
• Nuclear inspections
• Checking for land mines and bombs
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Introduction to Information Technology: Your Digital World
• Turing Test
• In 1950 Allen Turing predicted computers would
eventually be able to mimic human thinking
• Turing test determines whether the computer is
human
• Judge is in another location and doesn’t see the computer
• Judge converses via a computer terminal with two entities:
one a person and one a computer
• Judge must determine who is the person and who is the
computer
• If the computer can fool the judge, it is said to be
intelligent
• No computer system has yet passed the Turing test
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