Chapter 4 - Hardware, Software, Mobile Flashcards
Main Memory
Random Access Memory (RAM). The CPU reads data and instructions from memory, and it stores results of computations in main memory.
CPU
Central Processing Unit. The “brain” of the computer. Selects instructions, processes them, performs arithmetic and logical comparisons, and stores the results in memory.
Storage Hardware
Is used to save data and programs. Includes magnetic disks, like hard drives and USB thumb drives, and optical disks, like CD and DVD.
Server
A computer that is designed to support processing from many remote computers and users.
Server Farm
A collection of, typically, thousands of servers.
Clients
PCs, tablets, and smartphones that access servers and the cloud.
Binary Digits
Bits. A bit is either a zero or a one.
Byte
Bits are grouped into 8-bit chunks called bytes.
Kilobyte (K)
1,024 bytes.
Megabyte (MB)
1,024 kilobytes.
Gigabyte (GB)
1,024 megabytes.
Terabyte (TB)
1,024 gigabytes.
Petabyte (PB)
1,024 terabytes.
Exabyte (EB)
1,024 petabytes.
Hertz
Cycles per second. Used to measure CPU speed.
32-bit vs 64-bit processors
You need a 64-bit processor to effectively use more than 4GB of RAM.
Volatile vs Nonvolatile
The cache and main memory are volatile, meaning their contents are lost when power is off. Magnetic and optical disks are nonvolatile, meaning their contents survive when power is off.
Operating System
A program that controls that computer’s resources. Some of the functions of an OS are to read and write data, allocate main memory, perform memory swapping, start and stop programs, respond to error conditions, and facilitate backup and recovery.
Native Applications
Programs that are written to use a particular operating system. Sometimes called thick-client applications.
Thin-client
An application designed to run within a computer browser such as Firefox, Chrome, Opera, and Internet Explorer.
Windows
Most widely used operating system in business. Current version is Windows 8.1. Metro-style applications provide a touch interface.
Mac OS
First used by graphic artists and others in arts community; now used more widely. First desktop OS to provide a touch interface. Current version is Mac OS X Mavericks.
Unix
Popular on powerful client computers used in engineering, computer-assisted design, architecture. Difficult for the nontechnical user. Almost never used by business clients.
Linux
Open-source variant of Unix. Adapted to almost every type of computing device. Rarely used by business clients.
Symbian
Nokia, Samsung and other phones. Popular worldwide, but less so in North America.
Blackberry OS
Research In Motion Blackberries. Device and OS developed for use by business. Very popular in beginning, but strongly challenged by iPhone and others.
iOS
iPhone, iPod Touch, iPad. Rapidly increasing installed base with success of the iPhone and iPad. Based on Mac OS X.
Android
Linux based phone/tablet operating system from Google. Rapidly increasing market share.
Windows RT
Windows 8 for ARM devices. Mostly tablets, but some PCs too.
Windows Server
Businesses with a strong commitment to Microsoft.
Unix Server
Fading from use. Replaced by Linux.
Linux Server
Very popular. Aggressively pushed by IBM.
Virtualization
The process by which one computer hosts the appearance of many computers. One operating system, called the host operating system, runs one or more operating systems as applications. Those hosted operating systems are called virtual machines (vm). Each virtual machine has disk space and other resources allocated to it.
3 Types of Virtualization
- PC Virtualization
- Server Virtualization
- Desktop Virtualization
PC Virtualization
A PC hosts several different operating systems.
Server Virtualization
A server computer hosts one or more other server computers.
Desktop Virtualization
A server hosts many versions of desktop operating systems.
License
When you buy a computer program, you are not actually buying that program. Instead, you are buying a license to use that program.
Site License
Large organizations do not buy a license for each computer user. Instead they negotiate a site license, which is a flat fee that authorizes the company to install the product (operating system or application) on all of that company’s computers or on all of the computers at a specific site.
Horizontal-market Application
Software provides capabilities common across all organizations and industries. Word processors, graphics programs, spreadsheets, and presentation programs are all horizontal-market application software. These applications are purchased off-the-shelf, and little customization of features is necessary (or possible).
Vertical-market Application
Software serves the needs of a specific industry. i.e. Dental offices, auto mechanics, parts warehouses.
One-of-a-kind Application
Software is developed for a specific, unique need.
Firmware
Computer software that installed into devices such as printers, print servers, and various types of communication devices. It is installed in special read-only memory on the device.
GNU
Self-referential acronym meaning GNU Not Unix. It was a set of open-source tools based on Unix programs. It was developed in 1983 by Richard Matthew Stallman, the father of the open source movement.
Open Source
The source code for a program is available to the public. In a closed source project, the source code is highly protected and only available to trusted employees and carefully vetted contractors.
Source Code
Computer code written by humans and understandable by humans. Source code is compiled into machine code that is processed by a computer. Machine code is, in general, not understandable by humans and cannot be modified.
Mobile Systems
Informations systems that support users in motion. Mobile systems users access the system from any place, using any smart device, such as a smartphone, tablet, or PC.
Mobile Device
A small, light-weight, power-conserving, computing device that is capable of wireless connectivity. Mobile devices include smartphones, tablets, PDAs and small, light laptops.
Just-in-time Data
Data delivered to the user at the precise time it is needed.
User Interface (UI)
The presentation format of an application. It consists of windows, menus, icons, dialog boxes, toolbars, etc., as well as user content.
User Experience (UE)
Refers not only to the UI, but also to the way the application behaves within that UI.
Chrome (in the context of UI)
The visual overhead in a computer display. It is the windows, the menus, and other apparatus that drive the application. Because mobile screen size is often limited, modern mobile apps eliminate it a much as possible.
Direct Interaction
Using content to drive application behavior.
Context-sensitive Chrome
Chrome pops up in the display when appropriate. Ideally, no button or command name is ever shown in a disabled (grayed-out) state.
Roaming
Occurs when users move their activities across devices.
Push Data and Pull Data
Push Data is data that the server sends to, or pushes onto, the device. Pull data is data that the device requests from the server.
