AP Test - AP Computer Science Principles

Overflow

(type of error)

During the execution of a program, if value arrives at a number outside of the computer's well-defined range, it [computer] will experience an overflow error.

Round-off

(type of error)

Round-off error occurs when a computer is used to produce real number calculations, and results from the omission of the significant figure. The error is the difference between the calculated approximation of a number and its exact mathematical value [due to rounding].

Lossy

(compression)

Results in lost data and quality from the original version of image and audio files.

Lossless

(compression)

Reduces a [image or audio] file's size with no loss of quality. This process basically rewrites the data of the original file in a more efficient war. Due to no loss of quality, the resulting files are much larger than those compressed with Lossy.

Metadata

Metadata is data that provides information about other data.

Types of Metadata

Descriptive, structural, and administrative.

Sequencing

The computer will run the code in order, one line at a time from the top to the bottom of the program.

Selection

When only certain lines of code are preferred to be run only if a condition is met [otherwise these lines would be ignored], an IF statement is used — thus, selection.

Iteration

If one wants the computer to execute the same lines of code several times, a loop is used, running until a certain condition is met.

Types of Loops

For, while, and repeat loops.

Reasonable Time

Polynomial in the number of steps an algorithm takes in the worst case based on the input size.

Not Reasonable Time

Usually exponential in the number of steps; example: doubling every time the input grows by one.

Heuristic

"Rule of Thumb," or a good guide to follow when making decisions, referring specifically to algorithms. When programming software, the goal is to create the most efficient algorithms to accomplish various tasks. A heuristic process may include running tests, getting results by trial and error.

Undecidable

A problem that is so difficult there is no possibility of creating an algorithm that would be able to answer yes or no for all inputs.

Linear Search

A search that goes one by one, in order.

Binary Search

A search that starts in the middle and proceeds to go left or right based on the outcome; like looking for a word in a dictionary. Binary searches require the list to be sorted in order.

APIs

Application Programming Interface:

APIs are a set of subroutine definitions, protocols, and tools for building application software.

Citizen Science

A lot of people to help with a scientific project; ex. asking everyone around the world to count the butterflies they see in one day.

Cloud Computing

Using distributed calculations and/or storage for big data or a web application

Crowdsourcing

Creative Commons

Open Access

Moore's Law

Peer-to-Peer Networks

Digital Divide

Protocols

IP Address

DNS

Internet Engineering Task Force

Fault Tolerance