Module 2 Flashcards
What is a notational system?
One used to represent different
quantities or characters. Notational systems used to represent values and quantities include decimal, binary, and hexadecimal.
What is decimal notation?
Decimal is based on the principle of expressing ten different numbers using a single digit in the range 0 to 9.
What is place value?
Each digit as we move from right to left (from least to most significant) is worth the base number (ten) times
more than the preceding digit.
What is binary notation?
Binary is a numbering system where each single digit can express only two values, in the range 0 to 1. Each column is worth the base number (two) times more than the preceding column as we move from least to most significant (right to left).
What is hexadecimal notation?
The hex notation system enables you to express 16 different numbers using a single digit in the range 0 to F. In this notation, the letters A through F are used to express numbers larger than nine (which require two digits of decimal to express). Thus, A is 10, B is 11, C is 12, D is 13, E is 14 and F is 15.
What are bits and bytes?
The basic unit of computer data is the binary digit or bit, which can represent two values (zero or one). Computer memory and file sizes in Windows are measured in multiples of bits. The first multiple is the byte, which is eight bits. A double byte
is 16 bits.
What are the 5 main byte sizes?
■ KiloByte (KB)—1000 bytes (or 103 or 101010 bytes). Small files are often measured in KB.
■ MegaByte (MB)—10001000 bytes (or 1,000,000 bytes). Many files would be measured in megabytes.
■ GigaByte (GB)—10001000*1000 bytes (1,000,000,000 bytes). Gigabytes are usually used to talk about disk capacity.
■ TeraByte (TB)—1000 GB (1,000,000,000,000 bytes). Some individual disk units might be 1 or 2 terabytes but these units are usually used to describe
large storage networks.
■ PetaByte (PB)—1000 TB or 1015 bytes (1,000,000,000,000,000 bytes). The largest storage networks and cloud systems would have petabytes of
capacity.
What is throughput rate?
When data is transferred between components in the computer or between computers over a network, the throughput rate that a particular connection can sustain is measured in bits per second (bps).
What are the main throughput units?
■ Kbps (or Kb/s)—1000 bits per second. Older computer peripheral interfaces (or buses) and slow network links would be measured in Kbps.
■ Mbps (or Mb/s)—1,000,000 bits per second. Many internal computer interfaces have throughputs measured in Mbps. Wireless networks and
residential Internet links also typically have this sort of throughput.
■ Gbps (or Gb/s)—1,000,000,000 bits per second. The latest PC bus standards and networks can support this higher level of throughput.
■ Tbps (or Tb/s)—1,000,000,000,000 bits per second. This sort of capacity is found in major telecommunications links between data centers, cities, and countries.
What is the independent speed of a computer’s processor described in?
A computer’s internal clock and the speed at which its processors work is measured in units of time called Hertz (Hz). 1 Hz represents one cycle per second.
■ Megahertz (MHz)—1 million (1,000,000) cycles per second. Older PC bus interfaces and many types of network interface work at this slower
signaling speed.
■ Gigahertz (GHz)—1000 million (1,000,000,000) cycles per second. Modern CPUs and bus types plus fiber optic network equipment work at these
much faster speeds.
What are the 5 main data types?
■ Integers—these are whole numbers. For example: 5, 21, or 65536. An integer data type consumes 1 to 8 bytes of computer storage.
■ Floating-point numbers—this type can support decimal fractions such as 4.1, 26.4, or 5.62. A floating-point number (or just “float”) consumes between 4 and 8 bytes of storage. Note that the floating-point type could store a whole number too (4.0 for instance).
■ Boolean values—these are a special numeric data type indicating that something is either TRUE or FALSE (with a 1 or 0). They consume a single bit of storage.
■ Characters—a character (or char) is a single textual character, and can be a letter of the alphabet, a symbol, or, indeed, a numerical character. For
example: a, D, 7, $, @, #. These consume one byte of storage. Note that when a number is entered as a character data type, you cannot perform any mathematical operations on it.
■ Strings—a string is a collection of text characters. For example: XYZ, Hello world. There is no real limit on the amount of storage that can be used by a string. Generally, you define the string length when you define
the data type.
Why is data representation important?
When binary values (1s and 0s) are used for char and string data types, there must be some means of data representation by which different value bytes
map to letters, numbers, and symbols in a character set. There are two common ways of presenting character set data: ASCII and Unicode.
What is ASCII?
In ASCII (American Standard Code for Information Interchange), each number or character in a text file or string variable is represented by a seven- bit binary number. With seven bits of binary, you can express 128 different values (0 through 127).
What is Unicode?
ASCII, although widely adopted, is a very old standard (devised in early 1960s). More recently, Unicode has become more prevalent. Unicode enables you to handle character data and express that data across platforms in a uniform way.
Unicode comprises:
■ A set of code charts that handle visual reference.
■ A data encoding method.
■ A set of standard character encodings.
■ A set of reference data files.
■ Additional properties, including:
● Character properties.
● Rules to handle normalization, rendering, display order (for languages that display right to left instead of left to right). There are a number of different Unicode character encoding standards, including UTF-8, UTF-16, and UTF-32. UTF-8 is used by many websites.
What is a security control?
Designed to prevent, deter, detect, and/or recover from attempts to view or modify data without
authorization.
What is Return on Security Investment (ROSI)?
To calculate ROSI, you perform risk assessments to work out how much the loss of data would cost
your organization and how likely it is that data loss might occur. The use of security controls should reduce both the impact and likelihood of losses,
justifying the investment made.
What are some examples of security controls?
■ Backup—ensure that you maintain copies of your data and that these copies can be quickly and easily accessed when necessary.
■ Access control—your data might have a value to your business competitors. Therefore, it makes sense to try to control access to stored data. You can use the following technologies to control access:
● Permissions—most operating systems provide a number of methods with which you can assign permissions on data files to users and
groups of users.
● Usage restrictions—you can use rights management software to control what users can do with data files. For example, you can allow specified
users to read a file but not to copy or print a file.
● Data encryption—this means that data is encoded in some way that only a person with the correct key can read it. Even if someone obtained a copy of encrypted data, they would not be able to read it without the
key. This means that rather than try to protect the data, the security system only has to protect the key, which is smaller and easier to defend. Some operating systems offer the ability to encrypt data while it is at rest (when stored on a disk). You can also use technologies to
encrypt data when it is in transit between the nodes on a network.
● Firewalls—on a network, a firewall can control how hosts and network applications are accessible to one another.
■ High availability—it is often the case that temporary loss of access to data can lead to high costs for an organization. Consider a situation when financial transactions are not available to a banking institution. You can implement technologies that enable you to ensure your data is available in the event of one or several failures of hardware or software components
within your infrastructure. These technologies are referred to as fault tolerance.
What is Intellectual Property (IP)?
Often the most valuable information asset that an
organization owns. There are various different types of IP and different ways to protect them from theft.
What is copyright?
Automatic legal protection granted to certain types of work indicating that the copyright holder owns the right to control the use of the work, including rights of publication, distribution, or sale.
What is a trademark?
As copyright is not given to the selection of a name, if a company wants to promote its goods it will normally trademark its name and/or logo. A trademark
must be distinctive within the industry in which the company is selling goods and services. An ordinary trademark is indicated by the ™ symbol. A registered
trademark is indicated by ®.
What is a patent?
A patent is legal protection for some kind of invention. Unlike copyright, a patent can apply to an idea so long as the idea is original (or novel), useful, and distinctive or non-trivial. If you have registered the patent, you do not actually have to have made a copy of the invention or put it into practice. A patent must be applied for and registered; however, there is no automatic protection, as there is for copyright. A patent infringement is where someone uses, makes, sells, or imports your invention without your permission. It does not matter whether the use was intentional or not.
What is a digital product?
A digital product is one that is sold or distributed as binary computer data. Examples of digital products include software, computer games, ebooks, music
tracks, streaming video, video downloads, and so on.
What is Digital Rights Management (DRM)?
Digital Rights Management (DRM) systems have been invented to try to enforce “pay-per-use” for digital products. When you purchase a digital product, the vendor may license the file for use on a restricted number of devices. You generally need to use your account with the vendor to authorize and deauthorize devices when they change.
What are 2 examples of data-driven business decisions?
■ Production and fulfilment—analysis of things such as process flows, manufacturing and assembly, delivery and transportation networks, and ordering and billing systems provides the opportunity to make them more
productive (efficient). Better productivity reduces costs and can improve customer satisfaction.
■ Sales and marketing—information about individual consumers gleaned from web search and social media histories allows for personalized advertising. Large data sets of the same information aggregating the
activity of millions of consumers can be used to identify trends and develop products and services to meet changing demands and interests.
What are the 3 main components of data analytics?
■ Data is the raw values collected by the system. The system must have some way of tagging or normalizing these values, similar to the way that data is defined with different types, so that they can be used for
comparisons. For example, a web server might log whenever a page is visited and record information about the visitor, such as the time, the location, the type of browser, how long they spent viewing the page, or any link from the page that was clicked. All these things are data points with distinct types and formats.
■ Information is some level of summarization of the individual data points. For example, you could use the logs of page visits to work out how many unique visitors there were (as opposed to the same visitor viewing the page more than once).
■ Insights are things that inform meaningful business decisions. For example, from the information provided by the analysis of unique visitors, you may devise a plan to increase unique visitor numbers through better
marketing or page design.
What are the 3 main components of facilitating data-driven business decisions?
■ Data capture and collection—data points can be collected from many different sources. In the previous example, most of the data points come from web server log files. The Internet of Things facilitates the use of sensors attached to all kinds of components, packages, and appliances to capture huge amounts of raw data. As well as collecting the data, it must be stored and secured. A traditional way of storing data is a relational database, but such structured data stores are being replaced (or supplemented) by semi-structured data warehouses.
■ Data correlation—the information layer requires software to perform data correlation. This means analyzing the whole data set and finding connections and links between data points. For example, software may find a correlation between page visitors and the color schemes used on pages, with pages that are predominantly blue attracting more visitors than pages
that make more use of yellow. The ability of software to perform data correlation without much human intervention is being greatly boosted by the development of Artificial Intelligence (AI) and machine learning systems.
■ Meaningful reporting—to inform human decision making at the insights layer, the information identified by the analytics system must be presented in ways that humans can analyze and interpret. The system must support search and query tools plus charts and graphs and other ways to present information pictorially. There is also the security requirement; only authorized users should be able to query the information store.
What are applications?
Applications (or apps) are the software programs that let users do useful things with their computer, such as create and edit documents, browse websites, send email, watch videos, or play games.
What are the software installation best practices?
Read the accompanying documentation to verify:
■ That the software is compatible with your operating system.
■ That your computer hardware meets the application’s recommended system requirements.
■ Any special installation instructions or known issues.
■ That you have a valid agreement or license to install and use the product.
What is the End User License Agreement (EULA)?
The license governing the use of a software, often called the End User License Agreement (EULA). The terms of the license will vary according to the type of software, but the basic restriction is usually that the software may only be installed on one computer (single use license).
Usually, the software is activated using a product key, which will be a long string of characters and numbers printed on the box or disk case.
What are Client Access Licenses?
If a site has a large number of computers, these computers are often networked. This means that software bought under license can be installed
onto a network server so that all authorized users can access it without it being installed on each individual computer.
What are the 5 main types of purchasable licensing?
Historically, software licensing tended toward one-time purchases of licenses for a given number of devices or user seats. The one-time purchase price would give perpetual use of the software, though subsequent upgrades would normally involve a new license fee. This model is being replaced by subscription-based licensing, where organizations pay a per-user monthly
fee to get access to the software. In this model, upgrades are provided as part of the subscription.
Not all software is distributed using the commercial licensing or subscription models described above. Shareware, freeware, and open source licenses
represent some different ways of making applications available.
■ Shareware is software that you can install free of charge so that you can evaluate it for a limited period. If you decide to continue using the software after this period, you must register it, usually for a fee. When you register the software you often become entitled to extra features and support.
■ Freeware is software that is available free of charge.
■ Open source is software that also makes the program code used to design it available. The idea is that other programmers can investigate the program and make it more stable and useful. An open source license does not forbid commercial use of applications derived from the original, but it is likely to impose the same conditions on further redistributions.
What is productivity software?
Productivity software refers to applications that help users complete typical office tasks. Such tasks might include writing a letter or report, making a sales
presentation, or processing orders.
What is a spreadsheet?
A spreadsheet consists of a table containing rows, columns, and cells. When values are entered into the cells, formulas can be applied to them, enabling
complex calculations to be carried out. Spreadsheet packages can be used for many tasks including tracking and analyzing sales data and working on
company accounts.
What is visual diagramming software?
Diagrams are an important means of communicating or recording ideas or configurations clearly. Visual diagramming software assists the creation of
these by providing templates and shapes for different kinds of diagram. The user does not have to worry about creating icons or shapes; they can just drag
shapes from the template (or stencil) into the diagram and use the software tools to connect them appropriately.
What is a Personal Information Manager (PIM)?
PIM software provides features for storing and organizing information, such as contacts and calendar events and appointments.
What is a online workspace?
An online workspace is one where a file is hosted on a network, and users can sign in to get access to it. Different users might be assigned different
permissions over the document.
What is a Remote Desktop?
Remote Desktop allows a user to connect to a computer over a network. The remote desktop server runs on the target computer. The user starts a remote
desktop client application and enters the connection information. When the connection is established, the user can operate the remote computer’s desktop
via a window on their local computer.
What is Instant Messaging (IM)?
Instant Messaging (IM) software allows users to communicate in real time. Unlike with email, there is (virtually) no delay between sending and receiving a
message. Basic IM software allows for the transfer of text messages and can also be used for file attachments. These days, all IM applications facilitate
voice and video calls too.
