AP CSP: Unit 1 Digital Information

bit

bit

smallest pieces of information the computer can store

pixels

small dot of light that represents a color

byte

a unit of digital information that consists of 8 bits

integer

a number without a fractional component

overflow error

the number requires more bits than the computer can store leading to the computer truncating the number

floating-point representation

used for non-integers like fractions and irrational umbers - similar to scientific notation

roundoff error

ends infitine sequences by rounding to hte nearest floating point number resulting in the lower precivison of a number’s representaiton

encoding

mappings from a character to a binary number

ascii

each character is encoded using 7 bits - only includes letters from the English alphabet and a few symbols

unicode

a universal character set which assigned each a code point (hex number) and a name to each character

utf-8

used to encode unicode to binary - describes every character from the Unicode standard using 1-4 bytes

analog

continuous stream of varying data - continues in both the time and amplitude domain

sampling

taking a sample at regular time intervals to reduce the continue time domain into a series of discrete intervals - express the signal as a series of points

sampling rate

inverse of sampling interval: the number of samples in a unit of time

frequency

number of cycles per second - measured in Hz

quantization

reducing the continuous amplitude domain into discrete levels

quantization error

measured by comparing the actual signal value with he quantized value at each sampled point

bit depth

number of bits per sample