Big Idea 2: Data

is the smallest unit of information stored or manipulated on a computer; it consists of either zero or one.

are a collection of pixels. where each pixel consists of binary numbers.

is based on light.

are not often just black and white.

exists throughout a continuous interval of time and takes on a continuous range of values.

is a sequence of discrete symbols.

is recording an analog signal at regular discrete moments and converting them to a digital signal.

is useful in computing to save disk space, or to reduce the bandwidth used when sending data (eg, over the Internet).

is also an important consideration when it comes to backing up and archiving your important files, particularly for uploading over the Internet.

are those that can reconstruct the original message exactly from the compressed message, and lossy algorithms can only reconstruct an appsimation of the original message.

packs data in such a way that the compressed package can be decompressed, and the data can be pulled out exactly the same as it went in.

is another important area for lossless compression.

is a technique that does not decompress digital data back to 100% of the original.

high image compression loss can be observed in photos when enlarged

there is a difference between an MP3 music and a high-resolution audio file

moving frames of video can handle a greater loss of pixels compared to an image

is the process of obtaining data from a database or software such as a social media website so that it can transport it to another software (such as spreadsheets) designed to support online analytical processing.

is a pictorial representation, a diagram used to represent data.

represent data in points, lines, bars, pie charts, and scatter plots.

use pictures to represent values.

use either vertical or horizontal bars to represent the values.

use lines to represent the values.

represent the data with points, and then a best-fit line is drawn through some of the points.