APCS - Unit 1

bit

single unit of information in a computer, typically represented as a 0 or 1

byte

8 bits of data

binary

a system where numbers and values are expressed 0 or 1.

binary number system

positional numeral system employing 2 as the base and so requiring only two different symbols for its digits, 0 and 1, instead of the usual 10 different symbols needed in the decimal system.

decimal number system

consists of 10 single-digit numbers: 0, 1, 2, 3, 4, 5, 6, 7, 8 and 9

overflow error

Error from attempting to represent a number that is too large

round off error

Error from attempting to represent a number that is too precise. The value is rounded

digital data

Data that changes discreetly through a finite set of possible values.

analog data

Data with values that change continuously, or smoothly, over time. Some examples include music, colors or a painting, or position of a sprinter during a race.

sampling

A process for creating a digital representation of analog data by measuring the analog data at regular intervals called samples.

pixel

A type of data used for graphics or pictures

resolution

The number of pixels on a screen at the same time

RGB

uses varying intensities of (R)ed, (G)reen, and (B)lue light. Added together these intensities reproduce a broad array of colors.

data compression

the process (or processes) by which the size of shared or stored data is reduced.

lossless compression

A process for reducing the number of bits needed to represent something without losing information. This process is reversible
No data is lost between the original file and its compressed state.
Can be decompressed (or reverted) back into its original form

lossy compression

A process for reducing the number of bits needed to represent something in which some information is lost or thrown away.
Irreversible

intellectual property

work or invention that results from a person's creativity, and can be patented, copyrighted or trademarked.

creative commons

non-profit organization that exists to expand the range of creative works available for others to build upon and legally share.

open access

refers to a set of principles that seeks to provide free, online access to informational materials such as articles or books.

open source

allow for others to study them, change them and distribute newly created materials to anyone and for any purpose. Ex: Linux, Python

1

2^0

2

2^1

4

2^2

8

2^3

16

2^4

32

2^5

64

2^6

128

2^7

256

2^8

512

2^9

1024

2^10