Quiz 3

1. Monitors-there are two major categories of monitors: Cathode ray-tube or CRT and liquid crystal display, also known as flat-screen or LCD. Both measure screen size diagonally and connect to the computer via USB port or a conventional printer cord. The flat-screen monitor uses up less power and causes less eye strain. Speakers and Headphones-part of the sound card system that produces multimedia, speakers and headphones produce audio output. The range of audio equipment available to the average computer user is tailored to Skype users, gamers, movie and video enthusiasts, and musicians. Most headphones also include a microphone for input as well. Printer- are used to make hard copies of computer output. There are three different kinds of printers. Dot matrix is the oldest and since it is slow and rather noisy compared to laser and ink-jet printers it is no longer widely used. Laser printers are the most expensive, but are fast and quiet and ink jet printers are inexpensive to buy, but the paper and toner consumption makes up for the cheap retail price. Disks and External Drives- (which include rewritable CDs, DVDs, floppy disks and external hard drives are used as storage devices for data output. Data can be text, video, audio or graphics files. External memory drives are often portable depending on the size. Both disk drives and CDs can also be used as input devices.

2.

LCD Monitors or Liquid Crystal Display Monitors are entirely flat image area devices that provide distortion free images. Hallmarks of LCD Monitors include such characteristics as rich and bright colors, vibrant images and sensational clarity. At Super Warehouse our incredible selection of LCD Monitors is unmatched. Within individual sizes and types of LCD Monitors you'll also find the entire gamut of specification options like resolution, aspect ratio, brightness, contrast ratio, response time and color support among others. Both analog and digital connectivity options equip you with LCD Monitors that are useful for nearly every environment. We have 22" Widescreen LCD Monitors perfect for use at the office with superior options for graphic designers as well as those designed for the home with gamers in mind.



LCD screens had such a narrow field of view that merely leaning over a bit or just sitting up straight in the chair would produce obvious visual changes. This isn’t the case with newer displays, but it is worth noting that if you sit quite close to today’s larger panels your angle of view from one side to the other and from top to bottom can be great enough to produce colour shifts in objects simply though being in different parts of the screen. Although LCD technology is constantly improving, the increase in display sizes tends to make this somewhat of a ‘two steps forward, one step back’ situation, particularly with the very largest LCD panels now on offer. For example, despite using the the very best quality of LCD hardware available, this effect can still be seen in Apple’s 30in Cinema display. Making sure you sit at a reasonable distance from your screen can help reduce or even eliminate this, but it is something to remember if you do critical colour work on your Mac.



Plasma displays are bright (1,000 lux or higher for the module), have a wide color gamut, and can be produced in fairly large sizes—up to 150 inches (3.8 m) diagonally. They have a very low-luminance "dark-room" black level compared to the lighter grey of the unilluminated parts of an LCD screen (i.e. the blacks are blacker on plasmas and greyer on LCDs).[1] LED-backlit LCD televisions have been developed to reduce this distinction. The display panel itself is about 6 cm (2.5 inches) thick, generally allowing the device's total thickness (including electronics) to be less than 10 cm (4 inches). Plasma displays use as much power per square meter as a CRT or an AMLCD television.[citation needed] Power consumption varies greatly with picture content, with bright scenes drawing significantly more power than darker ones – this is also true of CRTs. Typical power consumption is 400 watts for a 50-inch (127 cm) screen. 200 to 310 watts for a 50-inch (127 cm) display when set to cinema mode. Most screens are set to 'shop' mode by default, which draws at least twice the power (around 500–700 watts) of a 'home' setting of less extreme brightness.[2] Panasonic has greatly reduced power consumption ("1/3 of 2007 models") [3][4] Panasonic states that PDPs will consume only half the power of their previous series of plasma sets to achieve the same overall brightness for a given display size. The lifetime of the latest generation of plasma displays is estimated at 100,000 hours of actual display time, or 27 years at 10 hours per day. This is the estimated time over which maximum picture brightness degrades to half the original value.[5]

Plasma display screens are made from glass, which reflects more light than the material used to make an LCD screen.[citation needed] This causes glare from reflected objects in the viewing area. Companies such as Panasonic coat their newer plasma screens with an anti-glare filter material.[citation needed] Currently, plasma panels cannot be economically manufactured in screen sizes smaller than 32 inches. Although a few companies have been able to make plasma EDTVs this small, even fewer have made 32in plasma HDTVs. With the trend toward larger and larger displays, the 32in screen size is rapidly disappearing. Though considered bulky and thick compared to their LCD counterparts, some sets such as Panasonic's Z1 and Samsung's B860 series are as slim as one inch thick making them comparable to LCDs in this respect.



High-definition television (or HDTV) is video that has resolution substantially higher than that of traditional television systems (standard-definition TV, or SDTV, or SD). HDTV has one or two million pixels per frame, roughly five times that of SD. Early HDTV broadcasting used analog techniques, but today HDTV is digitally broadcast using video compression.

Some personal video recorders (PVRs) with hard disk storage but without high-definition tuners are described as "HD", for "Hard Disk", which can be a cause of confusion.

3. The most common components are inside a system unit are:
The processor
The memory
Adapter cards e.g. sound card, modern card, video card, network card.
Ports
Drive bays
Power supply
4. Components of a Processor
Control unit -- responsible for supervising the operation of the entire computer system.
Arithmetic/logic unit (ALU) -- provides the computer with logical and computational capabilities.
Register -- a storage location inside the processor. The machine cycle is the name of the four operations of the CPU. The first step is to 'fetch' the program instuction/data from the memory. The second step is to 'decode', which means translate the instruction into instructions. Step three is to 'execute', carry out the instruction. Finally step four is to 'store', write the result back to memory.

5. A bit (short for binary digit) is the smallest unit of data in a computer. A bit has a single binary value, either 0 or 1. Although computers usually provide instructions that can test and manipulate bits, they generally are designed to store data and execute instructions in bit multiples called bytes. In most computer systems, there are eight bits in a byte. The value of a bit is usually stored as either above or below a designated level of electrical charge in a single capacitor within a memory device.

Half a byte (four bits) is called a nibble. In some systems, the term octet is used for an eight-bit unit instead of byte. In many systems, four eight-bit bytes or octets form a 32-bit word. In such systems, instruction lengths are sometimes expressed as full-word (32 bits in length) or half-word (16 bits in length).

In telecommunication, the bit rate is the number of bits that are transmitted in a given time period, usually a second.

A bit represents information, any information. Call it an information carrier. The minimum number of bits required to hold some data is a measure of how much information the data contains.

The ever classic example is: How much information is required to represent the outcome of flipping a coin. Assume we have an ideal coin, when flipped we expect the coin to land with equal numbers of heads and tails being visible; we never expect it to land on its edge and stand upright.

Flipping this ideal coin represents two equally likely outcomes: TAIL or HEAD. If the coin lands heads one can write down the bit value `1' to completely represent the outcome of the coin toss. This represents the amount of information held by a bit: zero or one. A bit represents one outcome of two equally likely alternatives from an experiment.

So a sequence of bits can represent a series of successive coin tosses.

6. Application software consists of programs designed to perform specific tasks for users. Application software can be used as a productivity/business tool; to assist with graphics and multimedia projects; to support home, personal, and educational activities; and to facilitate communications. Specific application software products, called software packages, are available from software vendors. Although application software also is available as shareware, freeware, and public-domain software, these usually have fewer capabilities than retail software packages.

The Key Features in Business programs in terms of software is editting and typing and other stuff knowing what letters to use like formating


8. Advantages of Web Applications
No special configuration or changes are need on user's PCs.
Lower costs.
Centralised data is secure and easy to backup.
Updates can be made quickly and easily.
Information is accessible to a wide audience anywhere in the world.
Available 24 hours a day, 7 days a week.
Everybody has a browser - familiar interface encourages use.
Online training can be completed at user's own time and pace.
Always up-to-date.

9.



The history of the Internet starts in the 1950s and 1960s with the development of computers. This began with point-to-point communication between mainframe computers and terminals, expanded to point-to-point connections between computers and then early research into packet switching. Packet switched networks such as ARPANET, Mark I at NPL in the UK, CYCLADES, Merit Network, Tymnet, and Telenet, were developed in the late 1960s and early 1970s using a variety of protocols. The ARPANET in particular led to the development of protocols for internetworking, where multiple separate networks could be joined together into a network of networks.

In 1982 the Internet Protocol Suite (TCP/IP) was standardized and the concept of a world-wide network of fully interconnected TCP/IP networks called the Internet was introduced. Access to the ARPANET was expanded in 1981 when the National Science Foundation (NSF) developed the Computer Science Network (CSNET) and again in 1986 when NSFNET provided access to supercomputer sites in the United States from research and education organizations. The ARPANET was decommissioned in 1990. Commercial internet service providers (ISPs) began to emerge in the late 1980s and 1990s and the Internet was commercialized in 1995 when NSFNET was decommissioned, removing the last restrictions on the use of the Internet to carry commercial traffic.

Since the mid-1990s the Internet has had a drastic impact on culture and commerce, including the rise of near instant communication by electronic mail, instant messaging, Voice over Internet Protocol (VoIP) "phone calls", two-way interactive video calls, and the World Wide Web with its discussion forums, blogs, social networking, and online shopping sites. The research and education community continues to use advanced networks such as NSF's very high speed Backbone Network Service (vBNS) and Internet2. Increasing amounts of data are transmitted at higher and higher speeds over fiber optic networks operating at 1-Gbit/s, 10-Gbit/s, or more. The Internet continues to grow, driven by ever greater amounts of online information and knowledge, commerce, entertainment and social networking.


10.

External Hard Drives

External Hard Drive


External hard drives are exactly the same as internal drives, with one exception. Rather then being enclosed inside your computer, external hard drives have their own separate casing and sit externally to your computer. External hard drives can connect to your computer in a variety of ways. Some common connection types are: USB 2.0, ESATA, Firewire 400 and Firewire 800. External hard drives measure capacity in gigabytes and have different speeds as well. For the most part, external hard drives are used for backup and storing files that a computer user may want to transport.


Network Attached Storage

NAS Server


Another common form of computer storage is network attached storage or NAS. Network attached storage is a method commonly used by businesses to share files between computers. A NAS is simply a storage device connected to a computer network. This is beneficial because many computers can read and write to a NAS. Network attached storage capacity is measured in gigabytes. Also, NASs are available with different hard drive speeds.

Many at home computer users often create their own NAS devices by connecting an external hard drive to their router. This allows them to access it wirelessly, as well as share it with other computers.


Optical Media Storage

Optical Drive


Optical media storage is basically writing data to a CD or DVD. When your burn a CD, you are storing songs and music on the CD so that you can listen to it later. If you are burning a DVD, you are storing a video on it so that you can watch it later. CD-RW and DVD-RW media has the capability to be recorded on and erased later if necessary. This makes optical media storage ideal for transporting relatively small amounts of data



External Hard Drives

External Hard Drive


External hard drives are exactly the same as internal drives, with one exception. Rather then being enclosed inside your computer, external hard drives have their own separate casing and sit externally to your computer. External hard drives can connect to your computer in a variety of ways. Some common connection types are: USB 2.0, ESATA, Firewire 400 and Firewire 800. External hard drives measure capacity in gigabytes and have different speeds as well. For the most part, external hard drives are used for backup and storing files that a computer user may want to transport.
Network Attached Storage

NAS Server


Another common form of computer storage is network attached storage or NAS. Network attached storage is a method commonly used by businesses to share files between computers. A NAS is simply a storage device connected to a computer network. This is beneficial because many computers can read and write to a NAS. Network attached storage capacity is measured in gigabytes. Also, NASs are available with different hard drive speeds.

Many at home computer users often create their own NAS devices by connecting an external hard drive to their router. This allows them to access it wirelessly, as well as share it with other computers.
Optical Media Storage

Optical Drive


Optical media storage is basically writing data to a CD or DVD. When your burn a CD, you are storing songs and music on the CD so that you can listen to it later. If you are burning a DVD, you are storing a video on it so that you can watch it later. CD-RW and DVD-RW media has the capability to be recorded on and erased later if necessary. This makes optical media storage ideal for transporting relatively small amounts of data.

Flash Drive


Flash drives, or thumb drives, are one of the newest forms of computer storage. These drives connect to any computer by way of USB. Often times, students as well as business professionals, use flash drives as a simple way to transport text documents to and from work, and to and from school. When flash drives were first released, storage capacity was rather limited. However, companies are now manufacturing flash drives with huge storage capacities, up to 64GB.