Information Systems: Concepts and Applications
Module 1: Information Systems in Business
Computer literacy is the skill in using productivity software, such as word processors, spreadsheets, database management systems, and presentation software, as well as having a basic knowledge of hardware and software, the Internet, and collaboration tools and technologies.
Information literacy is understanding the role of information in generating and using business intelligence.
Business intelligence (BI) provides historical, current, and predictive views of business operations and environments and gives organizations a competitive advantage in the marketplace.
Transaction-processing systems (TPSs) focus on data collection and processing; the major reason for using them is cost reduction.
A management information system (MIS) is an organized integration of hardware and software technologies, data, processes, and human elements designed to produce timely, integrated, relevant, accurate, and useful information for decision-making purposes.
Data consists of raw facts and is a component of an information system.
A database is a collection of all relevant data organized in a series of integrated files.
The process component of an information system generates the most useful type of information for decision making, including transaction-processing reports and models for decision analysis.
Information consists of facts that have been analyzed by the process component and is an output of an information system.
Information technologies support information systems and use the Internet, computer networks, database systems, POS systems, and radio-frequency-identification (RFID) tags.
Michael Porter’s Five Forces Model analyzes an organization, its position in the marketplace, and how information systems could be used to make it more competitive. The five forces include buyer power, supplier power, threat of substitute products or services, threat of new entrants, and rivalry among existing competitors.
Module 2: Computers and Their Business Applications
A computer is a machine that accepts data as input, processes data without human intervention by using stored instructions, and outputs information.
The central processing unit (CPU) is the heart of a computer. It is divided into two components: the arithmetic logic unit (ALU) and the control unit.
The arithmetic logic unit (ALU) performs arithmetic operations (+, –, *, /) as well as comparison or relational operations (, =); the latter are used to compare numbers.
The control unit tells the computer what to do, such as instructing the computer which device to read or send output to.
A bus is a link between devices connected to the computer. It can be parallel or serial, internal (local) or external. Internal bus enables communication between a video card and memory.
A disk drive is a peripheral device for recording, storing, and retrieving information.
A CPU case is also known as a computer chassis or tower. It is the enclosure containing the computer’s main components.
A motherboard is 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.
Input devices send data and information to the computer. Examples include a keyboard and mouse.
An output device is capable of representing information from a computer. The form of this output might be visual, audio, or digital; examples include printers, display monitors, and plotters.
Main memory 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.
An 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
Secondary memory, which is nonvolatile, holds data when the computer is off or during the course of a program’s operation. It also serves as archival storage.
Random access memory (RAM) is volatile memory, in which data can be read from and written to; it is also called read-write memory.
Cache RAM resides on the processor. Because memory access from main RAM storage takes several clock cycles (a few nanoseconds), cache RAM stores recently accessed memory so the processor is not waiting for the memory transfer.
Read-only memory (ROM) is nonvolatile; data cannot be written to ROM.
A 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.
Magnetic tape, made of a plastic material, resembles a cassette tape and stores data sequentially.
Optical discs use laser beams to access and store data. Examples include CD-ROMs, WORM discs, and DVDs.
A 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. 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.
A storage area network (SAN) is 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.
Network-attached storage (NAS) is essentially a network-connected computer dedicated to providing file-based data storage services to other network devices. A server is a computer and all the software for managing network resources and offering services to a network.
An operating system (OS) is 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.
Application software can be commercial software or software developed in house and is used to perform a variety of tasks on a personal computer.
Machine language, the 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.
Assembly language, 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.
High-level languages are machine independent and part of the third generation of computer languages. Many languages are available, and each is designed for a specific purpose.
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.
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.
Basic are based on a methodology called object-oriented programming (OOP). Two main parts of an OOP include objects and classes.
An object is an item that contains both data and the procedures that read and manipulate it. Examples include a person, an event, or a transaction.
A class defines the format of the object and the action that it performs.
Module 3: Data and Business Intelligence
A database is a collection of related data that is stored in a central location or in multiple locations.
A data hierarchy is the structure and organization of data, which involves fields, records, and files.
A database management system (DBMS) is software for creating, storing, maintaining, and accessing database files. A DBMS makes using databases more efficient.
In a sequential access file structure, records in files are organized and processed in numerical or sequential order, typically the order in which they were entered.
In a random access file structure, records can be accessed in any order, regardless of their physical locations in storage media. This method of access is fast and very effective when a small number of records need to be processed daily or weekly.
With the indexed sequential access method (ISAM), records can be accessed sequentially or randomly, depending on the number being accessed. For a small number, random access is used, and for a large number, sequential access is used.
The physical view involves how data is stored on and retrieved from storage media, such as hard disks, magnetic tapes, or CDs.
The logical view involves how information appears to users and how it can be organized and retrieved.
A data model determines how data is created, represented, organized, and maintained. It usually contains data structure, operations, and integrity rules.
In a hierarchical model, the relationships between records form a tree-like structure (hierarchy). Records are called nodes, and relationships between records are called branches. The node at the top is called the root, and every other node (called a child) has a parent. Nodes with the same parents are called twins or siblings.
The network model is similar to the hierarchical model, but records are organized differently. Unlike the hierarchical model, each record in the network model can have multiple parent and child records.
A relational model uses a two-dimensional table of rows and columns of data. Rows are records (also called tuples), and columns are fields (also referred to as attributes).
The data dictionary stores definitions, such as data types for fields, default values, and validation rules for data in each field.
A primary key uniquely identifies every record in a relational database. Examples include student ID numbers, account numbers, Social Security numbers, and invoice numbers.
A foreign key is a field in a relational table that matches the primary key column of another table. It can be used to cross-reference tables.
Normalization improves database efficiency by eliminating redundant data and ensures that only related data is stored in a table.
Structured Query Language (SQL) is a standard fourth-generation query language used by many DBMS packages, such as Oracle 11g and Microsoft SQL Server. SQL consists of several keywords specifying actions to take.
With query by example (QBE), you request data from a database by constructing a statement made up of query forms. With current graphical databases, you simply click to select query forms instead of having to remember keywords, as you do with SQL. You can add AND, OR, and NOT operators to the QBE form to fine-tune the query.
Create, read, update, and delete (CRUD) refers to the range of functions that data administrators determine who has permission to perform certain functions.
Database administrators (DBA), found in large organizations, design and set up databases, establish security measures, develop recovery procedures, evaluate database performance, and add and fine-tune database functions.
A data-driven Web site acts as an interface to a database, retrieving data for users and allowing users to enter data in the database.
A distributed database management system (DDBMS) stores data on multiple servers throughout an organization.
The fragmentation approach to a distributed DBMS addresses how tables are divided among multiple locations. There are three variations: horizontal, vertical, and mixed.
The replication approach to a distributed DBMS has each site store a copy of the data in the organization’s database.
The allocation approach to a distributed DBMS combines fragmentation and replication, with each site storing the data it uses most often.
In object-oriented databases, both data and their relationships are contained in a single object.
An object consists of attributes and methods that can be performed on the object’s data.
Encapsulation refers to the grouping into a class of various objects along with their attributes and methods—meaning, grouping related items into a single unit. This helps handle more complex types of data, such as images and graphs.
Inheritance refers to new objects being created faster and more easily by entering new data in attributes.
A data warehouse is a collection of data from a variety of sources used to support decision-making applications and generate business intelligence.
Extraction, transformation, and loading (ETL) refers to the processes used in a data warehouse. It includes extracting data from outside sources, transforming it to fit operational needs, and loading it into the end target (database or data warehouse).
Online transaction processing (OLTP) is used to facilitate and manage transaction-oriented applications, such as point-of-sale, data entry, and retrieval transaction processing. It generally uses internal data and responds in real time.
Online analytical processing (OLAP) generates business intelligence. It uses multiple sources of information and provides multidimensional analysis, such as viewing data based on time, product, and location.
Data-mining analysis is used to discover patterns and relationships.
A data mart is usually a smaller version of a data warehouse, used by a single department or function.
Business analytics (BA) uses data and statistical methods to gain insight into the data and provide decision makers with information they can act on.
Big data is data so voluminous that conventional computing methods are not able to efficiently process and manage it.
Tableau is a data visualization tool used for generating business intelligence. It is used to analyze data for generating trends using graphs and charts.
Power BI from Microsoft is a platform that allows a user to analyze and visualize data from different sources with different formats
Module 4: Personal, Legal, Ethical, and Organizational Issues
An acceptable use policy is a set of rules specifying the legal and ethical use of a system and the consequences of noncompliance.
Accountability refers to issues involving both the user’s and the organization’s responsibilities and liabilities.
Nonrepudiation is a method for binding all the parties to a contract.
Spam is an unsolicited e-mail sent for advertising purposes.
Cookies are small text files with unique ID tags that are embedded in a Web browser and saved on the user’s hard drive.
Log files, which are generated by Web server software, record a user’s actions on a Web site.
Fake news is news, stories, or hoaxes created to intentionally misinform or deceive readers. Creation and dissemination of fake news could have serious economic and social consequences.
Deepfakes are fake videos or audio recordings that look and sound just like the real thing.
The General Data Protection Regulation (GDPR) covers a series of laws in order to protect European Union (EU) citizens’ personal data including genetic data, health, racial or ethnic origin, and religious beliefs
Social media networking ethics advocates that social media should be open and provide fair access to all of its users
Business networking ethics advocates that in order to maintain a business network, not only should the organization provide open and fair access to all authorized users, it should also consider three types of networking, including utilitarian, emotional, and virtuous
Intellectual property is a legal umbrella covering protections that involve copyrights, trademarks, trade secrets, and patents for “creations of the mind” developed by people or businesses.
Cybersquatting is registering, selling, or using a domain name to profit from someone else’s trademark.
Information technology and the Internet have created a digital divide. Computers are still not affordable for many people. The digital divide has implications for education.
Virtual organizations are networks of independent companies, suppliers, customers, and manufacturers connected via information technologies so they can share skills and costs and have access to each other’s markets.
Green computing involves the design, manufacture, use, and disposal of computers, servers, and computing devices (such as monitors, printers, storage devices, and networking and communications equipment) in such a way that there is minimal impact on the environment.
Module 5: Protecting Information Systems
Spyware is software that secretly gathers information about users while they browse the Web.
Adware is a form of spyware that collects information about the user (without the user’s consent) to determine which advertisements to display in the user’s Web browser.
Phishing is sending fraudulent e-mails that seem to come from legitimate sources, such as a bank or university.
Pharming is directing Internet users to fraudulent Web sites with the intention of stealing their personal information, such as Social Security numbers, passwords, bank account numbers, and credit card numbers. The difference is that pharmers usually hijack an official Web site address, then alter its IP address so that users who enter the correct Web address are directed to the pharmers’s fraudulent Web site.
Baiting is similar to phishing attacks. What distinguishes it from phishing is the promise that the baiter gives to the recipient.
Similar to baiting, quid pro quo involves a hacker requesting the exchange of critical data or login information in exchange for a service or prize.
Keystroke loggers monitor and record keystrokes and can be software or hardware devices.
Sniffing is capturing and recording network traffic.
Spoofing is an attempt to gain access to a network by posing as an authorized user in order to find sensitive information, such as passwords and credit card information.
Computer fraud is the unauthorized use of computer data for personal gain.
Confidentiality means that a system must prevent disclosing information to anyone who is not authorized to access it.
Integrity refers to the accuracy of information resources within an organization.
Availability means that computers and networks are operating, and authorized users can access the information they need. It also means a quick recovery in the event of a system failure or disaster.
Fault-tolerant systems ensure availability in the event of a system failure by using a combination of hardware and software.
A virus consists of self-propagating program code that is triggered by a specified time or event. When the program or operating system containing the virus is used, the virus attaches itself to other files, and the cycle continues.
A worm travels from computer to computer in a network, but it does not usually erase data. Unlike viruses, worms are independent programs that can spread themselves without having to be attached to a host program.
A Trojan program contains code intended to disrupt a computer, network, or Web site, and it is usually hidden inside a popular program. Users run the popular program, unaware that the malicious program is also running in the background.
A logic bomb is a type of Trojan program used to release a virus, worm, or other destructive code. Logic bombs are triggered at a certain time (sometimes the birthday of a famous person) or by a specific event, such as a user pressing the Enter key or running a certain program.
A backdoor (also called a trapdoor) is a programming routine built into a system by its designer or programmer. It enables the designer or programmer to bypass system security and sneak back into the system later to access programs or files.
A blended threat is a security threat that combines the characteristics of computer viruses, worms, and other malicious codes with vulnerabilities found on public and private networks.
A denial-of-service (DoS) attack floods a network or server with service requests to prevent legitimate users’ access to the system.
Social engineering means using “people skills”—such as being a good listener and assuming a friendly, unthreatening air—to trick others into revealing private information. This is an attack that takes advantage of the human element of security systems.
Cryptojacking reduces the performance of the victim’s computer.
Biometric security measures use a physiological element that is unique to a person and cannot be stolen, lost, copied, or passed on to others.
A callback modem verifies whether a user’s access is valid by logging the user off (after he or she attempts to connect to the network) and then calling the user back at a predetermined number.
A firewall is a combination of hardware and software that acts as a filter or barrier between a private network and external computers or networks, including the Internet. A network administrator defines rules for access, and all other data transmissions are blocked.
An intrusion detection system (IDS) can protect against both external and internal access. It is usually placed in front of a firewall and can identify attack signatures, trace patterns, generate alarms for the network administrator, and cause routers to terminate connections with suspicious sources.
Physical security measures primarily control access to computers and networks, and they include devices for securing computers and peripherals from theft.
Access controls are designed to protect systems from unauthorized access in order to preserve data integrity.
A password is a combination of numbers, characters, and symbols that is entered to allow access to a system.
A virtual private network (VPN) provides a secure “tunnel” through the Internet for transmitting messages and data via a private network.
Data encryption transforms data, called plaintext or cleartext, into a scrambled form called ciphertext that cannot be read by others.
Secure Sockets Layer (SSL) is a commonly used encryption protocol that manages transmission security on the Internet.
Transport Layer Security (TLS) is a cryptographic protocol that ensures data security and integrity over public networks, such as the Internet.
A PKI (public key infrastructure) enables users of a public network such as the Internet to securely and privately exchange data through the use of a pair of keys—a public one and a private one—that is obtained from a trusted authority and shared through that authority.
Asymmetric encryption uses two keys: a public key known to everyone and a private or secret key known only to the recipient. A message encrypted with a public key can be decrypted only with the same algorithm used by the public key and requires the recipient’s private key, too. Anyone intercepting the message cannot decrypt it because he or she does not have the private key.
In symmetric encryption (also called secret key encryption), the same key is used to encrypt and decrypt the message. The sender and receiver must agree on the key and keep it secret.
Business continuity planning outlines procedures for keeping an organization operational in the event of a natural disaster or network attack.
Zero trust security is a relatively new security model that requires every person and every device that accesses a network must be secured regardless if it is within the organization or outside of it.
Module 6: Data Communication – Delivering Information Anywhere and Anytime
Data communication is the electronic transfer of data from one location to another.
Bandwidth is the amount of data that can be transferred from one point to another in a certain time period, usually one second.
Attenuation is the loss of power in a signal as it travels from the sending device to the receiving device.
In broadband data transmission, multiple pieces of data are sent simultaneously to increase the transmission rate.
Narrowband is a voice-grade transmission channel capable of transmitting a maximum of 56,000 bps, so only a limited amount of information can be transferred in a specific period of time.
Protocols are rules that govern data communication, including error detection, message length, and transmission speed.
A modem (short for “modulator-demodulator”) is a device that connects a user to the Internet.
Digital subscriber line (DSL), a common carrier service, is a high-speed service that uses ordinary phone lines.
Communication media, or channels, connect sender and receiver devices. They can be conducted or radiated.
Conducted media provide a physical path along which signals are transmitted, including twisted pair copper cable, coaxial cable, and fiber optics.
Radiated media use an antenna for transmitting data through air or water.
In a centralized processing system, all processing is done at one central computer.
In decentralized processing, each user, department, or division has its own computer (sometimes called an “organizational unit”) for performing processing tasks.
Distributed processing maintains centralized control and decentralized operations. Processing power is distributed among several locations.
The Open Systems Interconnection (OSI) model is a seven-layer architecture for defining how data is transmitted from computer to computer in a network, from the physical connection to the network to the applications that users run. It also standardizes interactions between network computers exchanging information.
A network interface card (NIC) is a hardware component that enables computers to communicate over a network.
A local area network (LAN) connects workstations and peripheral devices that are in close proximity.
A wide area network (WAN) can span several cities, states, or even countries, and it is usually owned by several different parties.
A metropolitan area network (MAN) is designed to handle data communication for multiple organizations in a city and sometimes nearby cities as well.
A network topology represents a network’s physical layout, including the arrangement of computers and cables.
The star topology usually consists of a central computer (host computer, often a server) and a series of nodes (typically, workstations or peripheral devices).
In a ring topology, no host computer is required because each computer manages its own connectivity.
The bus topology (also called “linear bus”) connects nodes along a network segment, but the ends of the cable are not connected, as they are in a ring topology.
A hierarchical topology (also called a “tree”) combines computers with different processing strengths in different organizational levels.
A controller is a hardware and software device that controls data transfer from a computer to a peripheral device (examples are a monitor, a printer, or a keyboard) and vice versa.
A multiplexer is a hardware device that allows several nodes to share one communication channel.
In a mesh topology (also called “plex” or “interconnected”), every node (which can differ in size and configuration from the others) is connected to every other node.
Transmission Control Protocol/Internet Protocol (TCP/IP) is an industry-standard suite of communication protocols that enables interoperability.
A packet is a collection of binary digits—including message data and control characters for formatting and transmitting—sent from computer to computer over a network.
Routing is the process of deciding which path to take on a network. This is determined by the type of network and the software used to transmit data.
A routing table, generated automatically by software, is used to determine the best possible route for a packet.
In centralized routing, one node is in charge of selecting the path for all packets. This node, considered the network routing manager, stores the routing table, and any changes to a route must be made at this node.
Distributed routing relies on each node to calculate its own best possible route. Each node contains its own routing table with current information on the status of adjacent nodes so packets can follow the best possible route
A router is a network connection device containing software that connects network systems and controls traffic flow between them.
A static router requires the network routing manager to give it information about which addresses are on which network.
A dynamic router can build tables that identify addresses on each network.
In the client/server model, software runs on the local computer (the client) and communicates with the remote server to request information or services. A server is a remote computer on the network that provides information or services in response to client requests.
In the two-tier architecture (the most common type), a client (tier one) communicates directly with the server (tier two).
An n-tier architecture attempts to balance the workload between client and server by removing application processing from both the client and server and placing it on a middle-tier server.
A wireless network is a network that uses wireless instead of wired technology.
A mobile network (also called a cellular network) is a network operating on a radio frequency (RF), consisting of radio cells, each served by a fixed transmitter, known as a cell site or base station.
Wireless Fidelity (Wi-Fi) is a broadband wireless technology. Information can be transmitted over short distances—typically 120 feet indoors and 300 feet outdoors—in the form of radio waves.
Worldwide Interoperability for Microwave Access (WiMAX)is a broadband wireless technology based on the IEEE 802.16 standards. It is designed for wireless metropolitan area networks and usually has a range of about 30 miles for fixed stations and 3–10 miles for mobile stations
Bluetooth, which can be used to create a personal area network (PAN), is a wireless technology for transferring data over short distances (usually within 30 feet) for fixed and mobile devices
Throughput is similar to bandwidth. It is the amount of data transferred or processed in a specified time, usually one second.
To improve the efficiency and quality of digital communications, Time Division Multiple Access (TDMA) divides each channel into six time slots. Each user is allocated two slots: one for transmission and one for reception. This method increases efficiency by 300 percent, as it allows carrying three calls on one channel.
To improve the efficiency and quality of digital communications, Code Division Multiple Access (CDMA) transmits multiple encoded messages over a wide frequency and then decodes them at the receiving end.
In data communication, convergence refers to integrating voice, video, and data so that multimedia information can be used for decision making.
Module 7:
Advanced Research Projects Agency Network (ARPANET) – a project started in 1969 by the U.S. Department of Defense that was the beginning of the Internet.
Blog (short for Weblog) – a journal or newsletter that is updated frequently and intended for the general public. Blogs reflect their authors’ personalities and often include philosophical reflections and opinions on social or political issues.
Directories – indexes of information based on keywords embedded in documents, which make it possible for search engines to find what you are looking for.
Discussion groups – usually for exchanging opinions and ideas on a specific topic, usually of a technical or scholarly nature. Group members post messages or articles that others in the group can read.
Domain Name System (DNS) protocol – A protocol where when information is transferred from one network to another, domain names are converted to IP addresses. Servers using this protocol (called DNS servers) maintain lists of computers’ and Web sites’ addresses and their associated IP addresses.
Extranet – a secure network that uses the Internet and Web technologies to connect intranets of business partners so communication between organizations or between consumers is possible.
Hypermedia – documents which include embedded references to audio, text, images, video, and other documents.
Hypertext – the embedded references in hypermedia document. They consist of links users can click to follow a particular thread (topic).
Hypertext Markup Language (HTML) – the language used to create Web pages. It defines a page’s layout and appearance by using tags and attributes. A tag delineates a section of the page, such as the header or body; an attribute specifies a value, such as a font color, for a page component.
Industrial IoT or IIoT – used to enhance manufacturing and industrial processes such as predictive maintenance and data analytics on factory floors.
Internet backbone – a foundation network linked with fiber-optic cables that can support very high bandwidth. It is made up of many interconnected government, academic, commercial, and other high-capacity data routers.
Internet – a worldwide collection of millions of computers and networks of all sizes. It is a network of networks.
Instant messaging (IM) – a service for communicating with others via a private “chat room” on the Internet.
Internet of Everything (IoE) – a Web-based development in which people, processes, data, and things are interconnected via the Internet using various means, such as RFID devices, barcodes, wireless systems (using Bluetooth and Wi-Fi), and QR codes.
Internet of Things (IoT) – the physical objects that are connected to the Internet and, therefore, to all the other physical objects.
Internet Relay Chat (IRC) – enables users in chat rooms to exchange text messages with people in other locations in real time.
Internet telephony – using the Internet rather than the telephone network to exchange spoken conversations.
Intranet – a network within an organization that uses Internet protocols and technologies (e.g., TCP/IP, which includes File Transfer Protocol [FTP], SMTP, and others) for collecting, storing, and disseminating useful information that supports business activities, such as sales, customer service, human resources, and marketing.
Navigational tools – used to travel from Web site to Web site—as in “surf” the Internet.
Newsgroups – typically more general in nature and can cover any topic; they allow people to get together for fun or for business purposes.
Podcast – an electronic audio file, such as an MP3 file, that is posted on the Web for users to download to their mobile devices—iPhones, iPods, and iPads, for example—or even their computers.
RSS (Really Simple Syndication) feeds – a fast, easy way to distribute Web content in Extensible Markup Language (XML) format. It is a subscription service, and new content from Web sites you have selected is delivered via a feed reader to one convenient spot.
Search engine – an information system that enables users to retrieve data from the Web by using search terms.
Smart home – automates many of the tasks that traditionally were handled manually by humans.
Social networking – a broad class of Web sites and services that allows users to connect with friends, family, and colleagues online as well as meet people with similar interests or hobbies
Uniform resource locators (URLs) – identify a Web page. A URL is the address of a document or site on the Internet. Also called universal resource locators.
Voice over Internet Protocol (VoIP) – the protocol used for Internet telephony.
Web 2.0 – the trend toward Web applications that are more interactive than traditional Web applications. Collaboration or e-collaboration is one of its key components
Wiki – a type of Web site that allows users to add, delete, and sometimes modify content.