Comp Apps Final- Fuentes- Rutgers

hardware

built out of wires, rollers and monitors

software

performs instructions stored in the computer's memory / computing algorithm

layered software

software stack, arranging software into layers, each component corresponds to the ones below; the stack grows overtime as people contribute

algorithm

sequence of steps with a purpose of obtaining a particular result; precise and systematic method for producing a specified result

abstraction

removing the basic concept, idea or process from a situation

program

specialized algorithm written using a particular programming language

analog

curved lines; cannot distinguish the components; continuous

digital

straight lines; distinguishable components; discrete; can reproduce with more fidelity

feedback

any indication that either the computer is still working or has completed the request

consistent interface

the same operations that show up across operation

ex- file-new, open, close, save etc.

new instance

any specific piece of info (image, month, document)

ex- new word doc

perfect reproduction

copying and pasting

perfect reproduction- digital information

because of the 2 digits 0 & 1, relying on these 2 numbers has more advantages such as the ability to be perfectly reproduced

perfect reproduction- exact duplicate

we can make another copy by duplicating the sequence ; digital is an improvement of analog

metaphors

an icon or image or concept used as a representative of or symbolic or a computation

ex- controlling volume is a metaphor for increasing or decreasing something

Graphical User Interface (GUI)

allows the use of icons or other visual indicators to interact with electronic devices

mnemonic

aid for remembering something

synchronous communication

requires the both the sender and the receiver are active at the same time

ex- telephone conversation

asynchronous communication

the sending and receiving occur at different times

ex- texting, post cards

broadcast communication

single sender and many receivers

ex- radio, tv

multicast communication

many receivers but the intended recipients are not the whole population

ex- magazines covering special topics

point-to-point

one specific sender, one specific receiver

ex- texting

client/server structure

interaction between my computer (the client) and the computer on which the webpage I want to access is stored (server)

IP Addresses (Internet Protocol)

a sequence of four numbers separated by dots (each number 0-255)

payload

what is being sent

TCP/IP (Transmission Control Protocol/Internet Protocol)

the sending process of packets between computers

WAN

wide area networks; networks designed to send information between 2 locations widely separated and not directly connected

LAN

local area networks; the interconnection when computers are close enough to be linked by a single cables

ISP (Internet Service Provider)

A company that provides customers access to the Internet.

Campus or Enterprise Network

internet-support communication within the organization, but they also connect to the internet by gateway

domain names

used to refer to computers; machines look up domain names to find corresponding IP addresses

world wide web

web servers and their files; significant because of the information contained in the files and the ability of the client and servers computers to process it

protocol

the http:// part ; tells computer how to handle file

server name

"blogs.uclc.uchicago.edu" part; gives the name of the server in domain hierarchy

page's pathname

"/cstc/files/2007/07/0_new_1_csci.gif" part; gives the pathname saying where to find the file

describing a web page by HTML

servers dont store the webpage we can see on our screens but rather the description that says how it should appear

advantages of describing a web page by HTML

requires less info; a browser can adapt better to your computer with a description vs the literal pixel-by-pixel description

HTML 5

hypertext markup language; newest and best WWW language

bold

....

italic

....

paragraph

.....

singleton tags

tags that is not paired and so does not have a matching end tag

ex-

required tags

<

<

>

>

&

&

W3C Markup Validation Service

checks to make sure you html does not violate any html5 rules

anchor tags

anchor text

including picture with image tags

absolute pathnames

An entire URL

Click to get their file

relative pathnames

Pages on the same site stored in the same or nearby folders.

-Local files

Click here for my file

going "deeper" in a folder

give the navigation paths to them; path begins in the folder where the reference is being made and refers to the contents of the folder with a slash

going "higher"in the hierarchy

dot-dot-slash; ../ refer to photos in the enclosing folder

styles

background color, p, text align, color

CSS

cascading styling sheets

crawlers

main job is to build an index, a list of tokens(words) associated with the page

query processor

user presents tokens to query processor which looks them up in the index

multiword searches

intersects the lists that each have the token

title

anchor text

highlighted linked text, which is inside tags, describes the page it links to

meta

web page creators can add a tase in the head section, which can give a several-sentence description to the content of the page

alt attributes

The tag has an alt attribute that gives a textual description; good source pf descriptive terms for the image

page ranks

Google made this in order to determine which pages are likely to be most important to you; computed by the crawler

advanced searches

specifies a logical relationship between the words it connects

AND

all words must be associated with the page for it to hit; use quotes to get that exact phrase to appear

OR

hits on pages associated with at least one, but possibly more words

NOT

specifying words that are not associated with the page

combining local operators

can combine operators using parenthesis;

ex- (marshmallow OR strawberry OR chocolate) AND sundae - requires one or more of the flavors and the word sundae is associated

site search

looking only on their site

filtered search

constraints used to pinpoint the pages we want

primary sources of information

person who has direct knowledge of the info

secondary sources of information

people who interview primary sources

tertiary sources of information

people who watch journalists on TV or read news-paper reports

authoritative sources of information

what experts say on the subject; respected organization

PandA representation

presence and absence; describing info that is "black" or "white";

bit

the information produced in one PandA observation

binary system

2 possible alternatives (0,1)

hexadecimal numbering system

base 16

0 1 2 3 4 5 6 7 8 9 A B C D E F

ASII

american standard code for information interchange; 7-bit standard

extended ASII

8-bits called a byte; IBM adopted it as a standard unit for memory

unicode

used to handle other languages; UTF-8 is the transformation format

metadata

information describing other information

digitizing color

Smallest Intensity=0000 0000

Largest Intensity=1111 1111

pixels

small points of colored light arranged in a grid to form a compute display

to represent a single pixel requires _ bytes

3

RGB lights

each pixel is formed by these colors (red, green, blue)

intensities

different amounts of light

white

highest intensity

black

absence of light

lighten up: changing colors

darker pixels has low values, lighter pixels have high values

increasing brightness

adding the same number to each sub pixel

changing contrast

adding smaller amount for dark pixels and larger amount for light pixels

Nyquist rule

a sampling rate must be at least twice as fast as the frequency

bit depth

using more bits yields a more accurate digitization

lossless

the original representation of 0s and 1s can be perfectly reconstructed

lossy

the original representation of 0s and 1s cannot be exactly constructed

luminance

sensitivity to small changes in brightness

chrominance

we are not sensitive to small changes in color

run-length encoding

uses binary numbers to specify how long the firs sequence is, and so on and so forth

bandwith

measure of how much information is transmitted per unit of time