WGU C182 Introduction to IT Exam

Information Technology - The technology used in creating, maintaining, and making information accessible. IT Professional Roles - Administration and Support System Administrator - Maintains all aspects of the system including hardware, software, and programming. Network Administrator - In charge of all aspects of the computer network Database Administrator - Focuses on the design, development, and support of database management systems (DBMSs). Security Administrator - Installs, configures, and administers firewall security to protect systems and proactively work to stop intrusions. Web Administrator - Installs, configures, maintains, secures, and troubleshoots web severs. Support IT Professionals - Help desk and training. Information - Processed data. DIKW Hierarchy - Defines the transition of data to information to knowledge to wisdom. (Data Information Knowledge Wisdom) Data in DIKW - The input directly received by the user (or computer). It is generally not usable until it has been converted into a relevant form. Information in DIKW - Having been inferred from data; one or more processes have been applied to the data to transform it into a more useful form. Knowledge in DIKW - Information that has been put to use; information placed into a context. Refined information such that the user of the knowledge is able to call forth only relevant portions of information when needed. Wisdom in DIKW - Provides a social setting to knowledge; an understanding of the "why". Can only come by having both knowledge and experience. Information Systems - A collection of data and information used to support the management of an organization. Also refers to the technical components and human resources that enable the assembly, storage, and processing of data and the delivery of information. This has existed for a lot longer than computers. Characteristics of Quality Data - Relevance - the data being used must apply directly to the decision being made Timely - data must be efficient and must be provided in a timely manner Thorough - the data must be complete Accurate - data should be captured only once, where possible and should be captured as close to the point of activity as possible. Reliable - data should reflect stable and consistent data collection processes across collections points and over time IPOS - The Input-Procession-Output-Storage Cycle Input - Raw data is entered by the user. Processing - Raw data is organized or structured for usefulness. Output - Information is output so user can see results. Storage - Processed information is stored for permanent record. Computer System - A collection of components that work together to meet the needs of the user; typically categorized as either hardware, software, networks, or users. Hardware - Physical components of a computer system which include the system unit and its components and peripheral devices; tangible aspects of the computer. Software - Computer programs that tell the computer what to do--how to execute commands and process information Network - A collection of computers and resources connected by various media so that they can communicate with each other. User - Those who use a computer. Software Categories - Systems Software and Applications Software Evolution of Users - First users were the engineers who built and programmed computers, then employees who had received specialized training were users, and now today, anyone and everyone can be a user. Protocol - Rules provided by which networks communicate with each other. TCP/IP - Transmission Control Protocol/Internet Protocol. Most commonly used protocol; is required of all computers that communicate over the Internet. Protocol Stack - A collection of protocols. TCP/IP is an example. Components of a Computer - CPU, Memory and Storage, Peripheral Devices CPU - Executes programs' instructions and commands various components in the computer. Referred to as the "chip". Memory - Stores the programs being executed and the data they are using. I/O Subsystem - All peripheral devices where long term storage devices are used. Bus - Permits information to move between each component; electrical channels that enable communication among the electronic components System Unit - Critical component of all computer based systems; consists of most of the hardware the computer needs in order to run; comes in a variety of shapes and sizes. Internal Components of the System Unit - Case, Internal Bays, Buses, Ports, Hard Drive, Motherboard, CPU, CPU Cooler, Memory Module (RAM), Power Supply Unit (PSU), Expansion Slots/Cards Parts of the CPU - Control Unit (CU) - retrieves the instructions and the raw data that is input and coordinates or controls the sending of those instructions and data to the ALU Arithmetic Logic Unit (ALU) - does the actual processing of the data; completing mathematical calculations and logical operations to process the data and converting the input of the keyboard text entry to output displayed on the screen System Clock - Controls the speed at which instructions are processed. RAM - Stands for Random Access Memory. It temporarily stores data before it is processed and sent to your screen or printer. It is volatile (means data or information stored disappears when the computer is turned off or loses power). You can choose the amount of RAM your computer has. Types of RAM - Dynamic RAM (DRAM) - typically called main memory Static RAM (SRAM) - cache memory and registers BIOS ROM - BIOS stands for Basic Input Output System; ROM stands for Read Only Memory. Typically stored in ROM chip on the motherboard. Is software not hardware, ("basic" operating system that runs when the computer is first turned on). Runs tests of memory and the CPU and initializes hardware components so that the actual Operating System can be loaded from the hard disk. Can't choose the amount or contents. 1st Generation of Computers - Vacuum tubes, relay switches, the need to program in machine language 2nd Generation of Computers - Transistor components, magnetic core memory, smaller size, easier to program, disk drives and drums, called mainframe computers 3rd Generation of Computers - Silicon chips (known as ICs - integrated circuits), reduced cost, called mini computers, networks introduced via dumb terminals 4th Generation of Computers - Single chip processor, called microcomputer, first personal computer, rudimentary computer graphics, home use Moore's Law - Doubling of transistor count roughly every 18 - 24 months (exponential increase); observation, not physical law Evolution of Storage - Punch cards, magnetic tape, hard disks, floppy disks, optical discs, flash memory, cloud storage Machine/Low-level Language - Written for a specific machine by the engineers who built and ran the computers; no need for OS since only one program could run at a time Assembly Language - Easier than machine but still required detailed, precise low level instructions Language Translator Programs - Function is to translate one program language into another; take source code and convert it to another form; source code by itself cannot be read by a computer Complier - Improve language translator; requires that the components of the software all be defined before compilation can begin; code is more effcient Structured Programming - Programmer is limited to high level control constructs such as while loops, for loops, and if/else statements and not allowed to use primitive GOTO statements Object Oriented Programming - Initially introduced in Smalltalk in 1970's and early 80's Interpreted Code - Runs inside a special environment; is better for testing Shell Scripting - Small programs that place Linux commands or DOS batch files into a file Local Computer - The computer that the user is using; physically present with Remote Computer - A computer being accessed over the network Network Hub - Connects multiple computers together; broadcasts the transmission, sending the data to every device in the network Network Switch - More functional than a hub; records and recognizes the local network addresses (MAC or IP) or all computers connected to it Router - Connects multiple networks together; can be used to directly connect computers to a network; will relay messages to computers with appropriate IP addresses Wireless Access Point - Can be connected to hub, switch, or router; many routers now also act as a wireless access point; sends out a wireless signal so computers on the network can connect without a cable Circuit Switched Network - Requires that a full pathway, or circuit, be est. before transmission can begin and maintained during the entire transmission Packet Switched Network - A message's pathway is only est. as it is sent; the choice of pathway is based on availability and amount of message traffic Workstations - Creates and maintains client network connections to remote servers Virtual Machine (VM) - A software emulator program that permits a computer user to use multiple computers and multiple platforms without the expense of purchasing multiple computers; allows a user to run software for different OS platform in their computer that would not otherwise be able to run that software; this allows multiple users on a network to access the software to support collaboration. Server - Computers that have greater hard disk storage, faster response time and are used to respond to request from other computers on the network Client-server Network - Contains one or more servers; client is a computer that will request information from another computer; server is a computer that takes requests and responds with the requested information; the software used facilitates communication with remote servers File Server - Sends files over the network at the request of clients. Responds over LAN, within one location/site. Support both application software and data files. Web Server - Stores data files (web pages) and programs (scripts). Responds from anywhere on the Internet. Database Server - Responds to queries by pulling from the database. Typically only to local clients. Print Server - Monitors print jobs Mail Server - Two email servers communicate with each other FTP Server - Like web server or file server in that requests are for files and responses are the files Point-to-Point Network - Link between two resources. Simplest for of a network. Limits how devices can communicate with each other Bus Network - Devices connected along a single cable. Size of network is restricted. Star Network - Each device is connected to a central devices such as a hub or switch. Ring Network - Each device is connected directly to its neighbors, and messages are forwarded from device to device until the proper destination is reached. Mesh Network - Every device is connected directly to every other device in the network. Domain Name Server (DNS) - Used to translate from an IP alias to an IP address Parts of URL (Uniform Resource Locator) - Protocol, Domain name, Resource/Filename Domain Name - Identifies the server on which the web page can be found Domain Name Parts - Top level domain (TLD) name and Host name Host Name - Identifies the organization that is responsible for the information on the page or provides the server space where the information is stored TLD(Top Level Domain) Name - Always ends with a period and a three or two letter extension which signifies the type of organization or country associated with the page Resource/Filename ID - Indicates the name of the file you are accessing, or the location of the document on the server CIA - Confidentiality, Integrity, Availability Confidentiality - Requires that data bet kept secure so that they are not accidentally provided or obtained by unauthorized users