CS 3

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Information Systems for Business and Beyond
Tim Lam
Note by Tim Lam, updated more than 1 year ago
Tim Lam
Created by Tim Lam over 4 years ago
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Page 1

Chapter 1: What is an Information System?

Information Systems: the study of complementary networks of hardware and software that people and organizations use to collect, filter process, create and distribute data. combinations of hardware, software, telecommunications networks that people build and use to collect, create, and distribute useful data, typically in organizational settings. A computer is an electronic device operating under the control of instructions stored in its own memory                            Accepts Data (Input) -> Processing -> Produces Information (output) A communications device is hardware capable of transferring items from computers and devices to transmission media and vice versa The Internet is a worldwide collection of computer networks that connects millions of businesses, government agencies, educational institutions, and individuals Green Computing involves reducing the electricity when consumed and environmental waste generated when using a computer Strategies include recycling Using energy-efficient hardware and energy-saving features regulating manufacturing processes

The FIVE components of IS Hardware: digital devices that you can physically touch Software: operating system software and application software Data: collection of facts People: an essential element Process: series of steps undertaken to achieve a desired outcome or goal

Technology: Hardware Software: a set of instructions that tells the hardware what to do Two main categories: operating software - makes the hardware useful ( ex: Microsoft Windows or Google's Android on a mobile phone) application software - does something useful (ex: Microsoft Excel and Angry Birds) Data

Mainframe Era (1950s - 1960s) first business computer (room-sized monsters) functions as data processing such as scientific calculation and accounting primary work was to organize and store large volumes of information that were tedious o manage by hand In the late 1960s, MRP (Manufacturing Resources Planning) systems were introduced MRP allowed companies to manage the manufacturing process; making it more efficient From tracking inventory to creating bills of materials to scheduling product MRP II systems gave businesses more reasons to integrate computing into their processes and making IBM the dominant mainframe company The PC Revolution (1975 - 1981) Alta 8800, the first microcomputer, is announced in 1975 Apple Computer, headed by Steve Jobs and Steve Wozniak, follows soon after 1981, IBM and Microsoft team up and release "PC" which uses Microsoft DOS as its operating system Client-Server (mid - 1980s) client-server network architecture was introduced to allow users to log in to the LAN from their PC (the client) by connecting to a powerful computer called a "server," which would then grant them rights to different resources on the network such as the shared files and a printer on the server. This spurred software companies to begin developing applications that allow multiple users to access the same data at the same time The first ERP (Enterprise Resource Planning) was developed to run to the client-server architecture An ERP system is a software application with a centralized database that can be used to run a company's entire business. German's SAP lead the way of ERP by integrating accounting, finance, inventory, human resources, and many more together The World Wide Web & E-Commerce (Invented in 1969) The internet was first invented in 1969 but was confined to use by universities, government agencies, and researchers the first e-mail messages were sent in the early 1970s, but companies who wanted to expand their LAN-based email started hooking up to the internet in the 1980s. In 1989, Tim Berners-Lee developed a simpler way for researchers to share information over the network t CERN laboratories, a concept he called the World Wide Web. This invention became the launching point for businesses to share information about themselves using web browsers and grab domain names to create websites. In 1991, the National Science Foundation lifted restrictions on its commercial use In 1995, eBay and 1994, Amazon established the new digital marketplace and led to the dot-com boom through the 1990s and then the dot-com bust in 2000 As more companies connected to the internet, the digital world became a more dangerous place with computer viruses now being able to spread with tremendous speed via the internet.  Web 2.0 Web 2.0 is a new type of interactive website where you did not how to create a web page or do any programming to in order to put information online Disintermediation - the process of replacing a middleman in a transaction The Post-PC World  After 30 years, PC sales begin to decline. The limited storage and processing power of these PC is being offset by a move to "cloud" computing, which allows for storage, sharing, and backup of information on a massive scale

Page 2

Chapter 2: Hardware

Digital Devices A digital device processes electronic signals that represent either a one ("on") or a zero ("off") The on state is represented by the presence of an electronic signal; the off state is represented by the absence of an electronic signal Each one or zero is referred to as a bit. A bit that is turned off represents 0 A group of 8 bits is a byte. it can generate a set of 128 numeric codes (2^8= 256 or 0-255) A byte represents one English character in ASCII code (American Standard Code for Information Interchange) Unicode uses two bytes (16 bits) to represent one character of any language in the world Understanding Binary, Decimal, Hex, Octal Binary is the base-two numbering system Decimal is e base-ten numbering system Hexadecimal is the base-sixteen numbering system Octal is the base-eight numbering system

A listing of Binary Prefixes Kilo (KB) - one thousand Mega (MB) - one million (one thousand kilo) Giga (GB) - one billion (one thousand mega) Tera (TB) - one trillion (one thousand giga)

Processing Data: The CPU The CPU (Central Processing Unit) can be thought of as the "brains" of the device The CPU carries out the commands sent to it by the software and returns results to be acted upon Processors contain a Control Unit and an Arithmetic Logic Unit  Control Unit - coordinates & controls all the other parts of a computer system Arithmetic Logic Unit (ALU) - the actual processing by performing mathematical & logical operations CPU contains registers that temporarily hold data and instructions The two primary manufacturers of CPUs for personal computers: Intel & AMD (Advanced Mirco Devices) The speed ("clock time") of a CPU is measured in hertz A hertz is defined as one cycle per second System Clock - regulates CPU's processing functions by emitting a pulse at the regular intervals The pace of the system clock is called the clock speed and is usually measured in gigahertz Besides a faster clock time, many CPU chips now contain multiple processors per chip such as dual-core and quad-core Word size is the number of bits the processor can interpret and execute at a given time

The Machine Cycle The Four Steps: Fetch the instruction from RAM; called a register Decode the instruction Execute the instruction Store the result back to RAM

Moore's Law Gordon Moore, one of Intel Founders, states in 1965 that the number of transistors on a chip will double every two years, which means computing power will double every two years, and the price of CPU will drop in half every two years Though many predicted its demise, Moore's Law held true for over forty years

Motherboard The motherboard is the main circuit board on the computer. The motherboard provides an electrical bus connection between different computer components. A bus allows the various devices both inside and attached to the system unit to communicate with each other. The bus is the electrical connection between different computer components The combination of how fast the bus can transfer data and the number of data bits that can be moved at one time determines the speed Bus width determines the number of bits that the computer can transmit at one time: 32-bit bus, 64-bit bus, and 128-bit bus Types of buses: System Bus (Front Side Bus - FSB) connects the processor to main memory Backside Bus (Backside Bus - BSB) connects the processor to cache Data Bus - carries information Address Bus - unique address of a location in the memory where data is stored Control Bus - determines its operation Expansion Bus moves information between internal components of a computer

Memory Memory consists of electronic components that store instructions waiting to be executed by the processor, data needed by those instructions, and the results of processing the data The system Unit contains two types of memory: Volatile memory is used while the program is running loses contents when power is turned off Example is RAM Nonvolatile memory is used to store BIOS configuration does not lose contents when power is turned off Examples include ROM, flash memory, and CMOS ROM - contents permanently burned in the chip Flash Memory - can be erased electronically and rewritten CMOS (Complementary metal-oxide-semiconductor) - technology that uses battery power to retain information when the power to the computer is off Virtual Memory - section of the disk used as a backup for RAM Random Access Memory (RAM) RAM (Random Access Memory) - An area of the computer that temporarily holds data and instructions for processing the data primary storage reusable volatile RAM is working memory and can transfer data faster than a hard disk Hard Disk A hard disk is where data is stored when the computer is turned off and where t is retrieved from when the computer is turned on A hard disk contains one or more inflexible, circular platters that use magnetic particles to store data instructions, and information Hard Disk is the secondary storage and can hold data when there is no power to the computer Solid-state Drives A relatively new computer component that performs the same function as a hard disk: long-term storage Uses flash memory instead of spinning disks, which is faster

Removable Media Allows you to take data with you Floppy Disks USB flash drives Optical disc External hard disk Memory card

Network Connection A network is a collection of computers and devices connected together via communications devices and transmission media In the mid-1980s, organizations began to see the value in connecting computers together via a digital network By the mid-1990s, a network port was standard on most PCs Many PCs began including wireless networking capabilities in the early 2000s

Input and Output Input devices enter data and instruction into the memory of a computer Input methods include: Keyboard mouse pointing devices monitor input scanners Output is data that has been processed into useful form Output methods include monitor printer speakers printers Bluetooth Bluetooth was first invented in the 1990s to exchange data over short distances of 100 to 150 feet using radio waves devices to communicate via Bluetooth, both the personal computer and the connecting device must have a Bluetooth communication chip installed

Other Computing Devices   Portable Computers In 1983, Compaq developed the first commercial portable personal computer with 28 pounds weight. This "luggage" computer has given way to a much lighter clamshell computer that weighs from 4 to 6 pounds and runs on batteries.  As technology advances, a new class of laptop is becoming the standard:  extremely light portable use less power than their lighter counterpart A good example is the MacBook Air; it weighs less than 3 pounds and is only 0.68 inches thick Smartphones The first modern-day mobile phone was invented in 1973 Resembles a brick it weighs 2 lbs and costs $4,000  The first smartphones were: The IBM Simon; introduced in 1994 Apple's iPhone; released in January 2007 Andriod phone; released in 2008 Tablet Computers A tablet computer is one that uses a touch screen generally have no keyboard ranges in size from handheld PDAs to full-size 14-inches devices The early tablets were a commercial failure but in January 2010, Apple introduces the iPad and sales took off Integrated Computing Computing technology is being integrated into many everyday products such as the smart house and self-driving car

The Commoditization of the Personal Computer The PC has been a commodity because there is very little differentiation between computers from various companies and the primary factor that controls their sale is their price, which results in a very thin profit margin However, this case does not apply to the computer brand, Apple Apple created their own niche by making their PC unique and difficult to copy because everything is proprietary

The Problem of Electronic Waste Where does this electronic debris end up? In developing countries, it ends up in dumps and become health hazards for those living near them

Page 3

Chapter 3: Software

Types of Software: Operating systems - manage the hardware and create the interface between the hardware and the user Application software - the category of programs that do something useful for the user

Operating Systems The operating systems provide several essential functions: manage the hardware resources of the computer provide the user-interface components provide a platform for software developers to write applications Some operating systems are  Microsoft Windows Apple's OS X / iOS Google's Android In 1984, Apple introduced the Macintosh, featuring an operating system with a graphical user interface. It was the first graphic user interface to find commercial success. In 1985, Microsoft released the first version of Windows. It was an application that ran on top of the DOS OS to provide a graphical environment. (not true GUI) In 1990, Mircosoft released Windows 3.0 with the true GUI (Graphic User Interface) and business users began using GUI ushering us into the graphical-computing era Early Operating System IBM's DOS (Disk Operating System)developed by Microsoft Single user operating system allows multiple users to log in by logging out the previous login user DOS didn't provide multitasking. It allowed you to run multiple applications by closing out the previously running application Command base - must type command to initiate an action limited amount of memory, making it impractical to run large programs Newer Operating System Multitasking allows multiple users to login without logging out the previous login user Virtual memory uses part of the hard drive space to function as memory space Multi-users allows multiple users to login without logging out the previous login user Voice input UNIX and Linux (Linn-ex) UNIX is primarily used by scientists and engineers on a larger microcomputer that is very expensive Linux is a version of the UNIX operating system that runs on the PC. Linux is an open-sourced operating system developed by Linus Torvald with an objective to run UNIX on less expensive PC Mac vs Windows Apple has been the favorite of artists, musicians, and the technology elite. Apple also provides a lot of computers to elementary schools, thus gaining a following among the younger generation. Microsoft found itself with the dominant personal-computer operating system for business. As we learned, most businesses used mainframe in the 1960s and 1970s. In 1981, IBM introduced a PC using Microsoft’s DOS to their business clients. Therefore, when Microsoft released Windows as the next iteration of DOS, companies took the safe route and started purchasing windows. As the networked personal computer began to replace the mainframe computer as the primary way of computing inside businesses, Microsoft developed business-level server products to go along with their personal computer products, thereby providing a complete business solution.

Application Software  Application software is, essentially, software that allows the user to accomplish some goal or purpose Utility Software - allows you to fix or modify your computer in some way disk fragmentation antivirus software Programming Software - a software whose purpose is to make more software. It provides programmers with an environment in which they can write code, test it, and convert int into the format that can be run on a computer Application for Enterprise In the 1990s, the ERP (Enterprise Resource Planning) system was developed to bring together an entire organization in one software application ERP system is a software application utilizing a central database that is implemented throughout the entire organization. Some well-known ERP systems are SAP, Oracle, and Microsoft ERP brings an organization a good return of investment as a form of business process competitive advantage Y2K and ERP Application development began in the 1960s. Those days, computing is very expensive. To save resources, the programmer allots two digits instead of four digits to hold the year and assumed that the first two digits were “19” As the year 2000 approached, many of these legacy applications were still being used. In order to solve this problem, the application would be updated to use four digits for the year instead of two. This is where companies gained additional incentive to implement an ERP system. Some ERP systems include: CRM module (Customer Relationship Management) -  is a software application designed to manage an organization’s customers SCM module (Supply Chain Management) - is a software application designed to manage the linkage between an organization’s supplier, its manufacturing facilities, and distributors of its products. The number of links = # of suppliers * # of manufacturing * # of distributors Mobile Application  A mobile app is a software application programmed to run specifically on a mobile device These days, most mobile devices run on one of two operating systems: Android or iOS Android is an open-source operating system purchased and supported by Google iOS is Apple’s mobile operating system Because each application takes several thousand dollars to create and it can only run on specific platform, many companies have decided to create a website that is mobile-friendly and costs about the same but can be accessed by all mobile devices

Cloud Computing "The cloud" refers to applications, services, data storage on the Internet Many organizations are nervous about giving up control of their data and some of their application by using cloud computing. A solution to this problem lies in the concept of a private cloud. The basic idea is for the cloud service provider to section off web server space for a specific organization One technology that is utilized extensively as part of the cloud is "virtualization" Virtualization - is the process of using software to simulate a computer or some other devices such as VMWare Advantages of Cloud Computing No software to install or upgrade to maintain Available from any computer that has access to the Internet Can scale to a large number of users easily New applications can be up and running very quickly Services can be leased for a limited time on an as-needed basis Your information is not lost if your hard disk crashes or your laptop is stolen You are not limited by the available memory or disk space on your computer Disadvantages of Cloud Computing Your information is stored on someone else’s computer – how safe is it? You must have Internet access to use it. If you don't have access, you’re out of luck You are relying on a third-party to provide these services

Software Creation Modern software applications are written using a programming language A programming language consists of a set of commands and syntax that can be organized logically to execute specific functions A programmer writes a program (called the source code) that can then be compiled into machine-readable form, the ones and zeros necessary to be executed by the CPU

Open-Source Software and Closed-Source Software Open-Source software - is software that makes source code available for anyone to copy and use Benefits of the open-source model are: The software is available for free The software source code is available The large community of programmers who work on open-source projects leads to quick bug-fixing and feature additions Closed-Source software - source code that is not made available to others Benefits of the closed-source model are: By providing a financial incentive for software development, some of the brightest minds have chosen software development as a career Technical support from the company that developed the software  

Page 4

Chapter 4: Data and Databases

Data, Information, and Knowledge Data - are raw bits and pieces of information with no context Data can be quantitative (numeric) or qualitative (descriptive) Additionally: The count of data is information. The number of smokers that have lung cancer is information Consumption of information produces knowledge. Most lung cancer patients are smokers. This knowledge can be used to make decisions, set policies, and even spark innovation. Knowledge puts data into context. Wisdom combines knowledge and experience to produce a deeper understanding of a topic

Database A database - is an organized collection of related information. Databases are not always digital; a filing cabinet might be considered a form of a database. All information in a database should be related as well; separate databases should be created to manage unrelated information Databases can be organized in many different ways, and thus take many forms. The most popular form of database today is the relational database. A relational database - is one in which data is organized into one or more tables. All the tables are related by one or more fields so that it is possible to connect all the tables in the database through the field(s) they have in common. For each table, one of the fields is identified as a primary key Each table has a set of fields (columns), which define the nature of the data stored in the table A record (row) is one instance of a set of fields in a table Designing a Database Represent Entities as Tables - Determine the number of tables needed to be created The textbook example has four tables: Clubs, Students, Memberships, and Events Determine the Relationship - relationships connect the tables together One to many: one student can join many clubs, each event can have many students participate List Fields - Determine the specific information that each table will hold Students table five specific information: ID, First name. Last name, email, year of birth Identify Key - Determine a primary key for each table Student is a primary key: unique, minimal, not null, non-updateable Determine data type – Describe the kind of information that may be stored Text, number, yes/no, date/time, currency Normalization In simpler terms, to normalize a database means to design it in a way that reduces duplication of data between tables gives the table as much flexibility as possible Data Types  One of the important reasons to define a data type is so that the proper amount of storage space is allocated for the data Text Number Yes/ No Date/ Time Currency Two important reasons why we must properly define the data type of a field: a data type tells the database what functions can be performed with the data the second important reason to define data type is so that the proper amount of storage space is allocated for our data

Database and Spreadsheet Many times, when introducing the concept of databases to students, they quickly decide that a database is pretty much the same as a spreadsheet. After all, a spreadsheet stores data in an organized fashion, using rows and columns, and looks very similar to a database table. A database allows data from several entities (such as students, clubs, memberships, and events) to all be related together into one whole. While a spreadsheet does allow you to define what kinds of values can be entered into its cells. Databases provide more intuitive and powerful ways to define the types of data that go into each field, reducing possible errors and allowing for easier analysis.

Structured Query Language Almost all applications that work with databases (such as database management systems, discussed below) make use of SQL as a way to analyze and manipulate relational data. As its name implies, SQL is a language that can be used to work with a relational database Here is an example: SELECT "First Name", "Last Name" FROM "Students" WHERE "Students.ID" =

Other Types of Databases Hierarchical database model allows a parent/ child relationship between data Relational database model The new developmental concept of NoSQL (Not Only SQL) to allow working with data in a looser way Traditionally, for a relational database to work properly, it is important that only one person be able to manipulate a piece of data at a time, a concept known as record-locking Object orientated database model is the first database to allow programs (methods), and not just data, to be stored on the database

Data Management System DBMS packages generally provide an interface to view and change the design of the database, create queries, and develop reports Single-user at a time database Apache OpenOffice.org Base can be used to create, modify, and analyze databases in open-database (ODB) format Microsoft’s Access DBMS is used to work with databases in its own Microsoft Access Database format Enterprise database accessed by a group of people at a time Oracle, Microsoft, IBM, Open-source MySQL are some examples of enterprise database Google now offers the App Engine Database, which is based on NoSQL Amazon offers RDS (Relational Database Service) and Dynamic DB (a NoSQL enterprise solution.)

Big Data The term refers to such massively large data sets that conventional database tools do not have the processing power to analyze them For example, Walmart must process over one million customer transactions every hour. Storing and analyzing that much data is beyond the power of traditional database-management tools

Metadata The term metadata can be understood as "data about data" For example, when looking at one of the values of Year of Birth in the Students table, the data itself may be “1992″. The metadata about that value would be the field name Year of Birth, the time it was last updated, and the data type (integer).

Data Warehouse The concept of the data warehouse is simple: extract data from one or more of the organization’s databases and load it into the data warehouse for storage and analysis A data warehouse should be designed so that it meets the following criteria: It uses non-operational data The data is time-variant The data is standardized In order for the data warehouse to match up dates, a standard date format would have to be agreed upon all data loaded into the data warehouse would have to be converted to use this standard format This process is called extraction-transformation-load (ETL). The Benefits if Data Warehouses: The process of developing a data warehouse forces an organization to better understand the data that it is currently collecting and, equally important, what data is not being collected A data warehouse provides a centralized view of all data being collected across the enterprise and provides a means for determining data that is inconsistent Once all data is identified as consistent, an organization can generate one version of the truth. This is important when the company wants to report consistent statistics about itself, such as revenue or number of employees By having a data warehouse, snapshots of data can be taken over time. This creates a historical record of data, which allows for an analysis of trends A data warehouse provides tools to combine data, which can provide new information and analysis

Data Mining Data mining is the process of analyzing data to find previously unknown trends, patterns, and associations in order to make decisions Privacy Concern Data broker combines publicly accessible data with information obtained from the government and other sources to create vast warehouses of data about people and companies that they can then sell Business Intelligence and Business Analytics The term business intelligence is used to describe the process that organizations use to take data they are collecting and analyze it in the hopes of obtaining a competitive advantage Business analytics is the use of internal data to improve business processes and practices Knowledge Management Knowledge Management (KM) is the process of formalizing the capture, indexing, and storing of the company’s knowledge in order to benefit from the experiences and insights that the company has captured during its existence

Page 5

Chapter 5: Networking and Communication

A Brief History of the Internet In the late 1950s, the U.S. was in the depths of the Cold War with the USSR  In 1957, USSR launched sputnik. In response, the U.S. created ARPA (Advanced Research Project Agency) that is now called DARPA (Defense Advanced Research Project Agency) In September 1969, the ARPANET was turned on. The first four nodes were at UCLA, Stanford, MIT, and the University of Utah. Over the next decade, different organizations were connected to different networks. Each network used its own proprietary language or protocol to send information back and forth. The invention of transmission control protocol/Internet protocol (TCP/IP) solved the problem of computers being unable to talk to each other. It was from this breakthrough that we got the term Internet. TCP/IP was designed to allow network running on a different protocol to have an intermediary protocol that would allow them to communicate.   Protocol is the set of rules that allow two or more devices to exchange information back and forth across the network

Internet Vocabulary   Packet: The fundamental unit f data transmitted over the internet.  Hub: A simple network device that connects other devices to the network and sends packets to all the devices connected to it. Bridge: A network device that connects two networks together and only allows packets through that are needed. Switch: A network device that connects multiple devices together and filters packets based on their destination within the connected devices. Router: A device that receives and analyzes packets and then routes them towards their destination. IP Address: Every device that communicates on the Internet, whether it be a personal computer, a tablet, a smartphone, or anything else, is assigned a unique identifying number called an IP (Internet Protocol) address. Domain Name: A human-friendly name for a device on the Internet. DNS (Domain Name System): Acts as a directory on the Internet. When a request to access a device with a domain name is given, a DNS server is queried. It returns the IP address of the device requested, allowing for proper routing. Packet-Switching: When a packet is sent from one device out over the Internet, it does not follow a straight path to its destination. Instead, t is passed from one router to another across the Internet until t reaches its destination. In fact, sometimes two packets from the same message will take different routes! Sometimes, packets will arrive at their destination out of order.

Accessing the Internet Using the Internet in the early days, you had to know how to type in the commands necessary to access it, as well as know the name of the device In 1990, Tim Berners-Lee introduced his World Wide Web project, which provided an easy way to navigate the Internet through the use of linked text (hypertext) In 1993, Mosaic browser introduced an easy way to navigate the Internet and a way to present information by combining graphics and text together  In 1994, Mosaic was soon superseded by Netscape Navigator (The first commercial web browser)  

The Dot-Com Bubble In the 1980s and early 1990s, the Internet as managed by the National Science Foundation (NSF) who had restricted commercial ventures on the Internet In 1991, the SNF transferred its role to three other organizations, thus getting the US government out of direct control over the Internet and essentially opening up commerce online The new dot-com companies took place in the late 1990s, running up the stock market to new highs on a daily basis In 2000 and 2001, the bubble burst and many of these new companies went out of business. Many companies also survived, including the still thriving company Amazon (started in 1994) and eBay (1995)

Web 2.0 The early Web 2.0 allowed anyone with something to say a place to go and say it, without the need for understanding HTML or web-server technology Starting in the early 2000s, Web 2.0 application began the second bubble of optimism and investment. Myspace (2003), Photobucket (2003), Facebook (2004), and Twister (2006) are some examples of Web 2.0

"Killer" App for the Internet When PC was created, it was a great little toy When spreadsheet was invented, business took notice When email was invented, it began driving demand for the Internet We are seeing this once again today with social networks such as Facebook 

The Internet and the World Wide Web are Not the Same Thing The Internet is an interconnected network of networks  The World Wide Web is simply one piece of the Internet. It is made up of web servers that have HTML pages that are being viewed on devices with web browsers. Email, voice and video, and file transfers are some examples of the World Wide Web The Internet comes first, and the Web comes later

The Growth of Broadband In the early days, the speed of connection is about 1200 bps to 56,000 bps A broadband connection is defined as one that has a speed of at least 256,000 bps The average home broadband speed is between 3 mbps and 30 mbps

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