AP Computer Science Principles EXAM
Overflow correct answerserror that results when the number of bits is not enough to hold the number,
like a car's odometer "rolling over"
Round-off correct answerserror that results when the number of bits is not enough to represent the
actual number, like 3 digits to represent π as 3.14
Lossy correct answersCompressing data in a way that throws some data away and makes it almost
impossible to recover the original, great compression, like JPEG images
Lossless correct answersCompressing data in a way that preserves all data away and allows full recovery
of the original, good compression -- usually not as good as lossy, like PNG images
Metadata correct answersdata about data, like a camera storing the location, aperture, shutter speed,
etc. for a digital photo
Sequencing correct answerscode flows line by line, one after another, like a recipe
Selection correct answersa boolean condition to determine which of two algorithmic paths are taken,
aka if-then
Iteration correct answersusing a looping control structure, like while, for, foreach, repeat, repeat-until,
etc.
Reasonable Time correct answerspolynomial in the number of steps an algorithm takes in the worst case
based on the input size
Not reasonable time correct answersUsually exponential in the number of steps, like doubling every time
your input grows by one
,Heuristic correct answersusing a "rule" to guide an algorithm, like always walking toward the north star if
you were stuck in a forest
Undecidable correct answersA problem that is so difficult, we can't ever create an algorithm that would
be able to answer yes or no for all inputs, like determining if a user's program run on some input would
always stop and not run forever
Linear Search correct answersGoing one by one vs starting in the middle and going left/right like looking
for a word in the dictionary
Binary Search correct answersrequires the list to be sorted in order and then cutting the list in half
APIs correct answersApplication Programming Interface
Citizen Science correct answersLots of people to help with a scientific project, like asking everyone
around the world to count the butterflies they see one day
Cloud Computing correct answersUsing distributed calculations and/or storage for big data or a web
application
Crowdsourcing correct answersAsking lots of users online to help with something, like funding a project,
or running SETI@Home to help look for extraterrestrial signals
Creative Commons correct answersAn alternative to copyright that allows people to declare how they
want their artistic creations to be shared, remixed, used in noncommercial contexts, and how the policy
should propagate with remixed versions
Open Access correct answersA policy that allows people to have read access to things, e.g., libraries or
online data
Moore's Law correct answersThe # of transistors on a chip doubles every two years
, Peer-to-peer Networks correct answersA system where one user's computer connects through the
Internet to another user's computer without going through an intermediary "centralized" computer to
manage the connection
Digital Divide correct answersThe idea that some communities / populations have less access to
computing than others
ISP correct answersInternet Service Provider
How does internet communication arrive at its destination? correct answersSpeech on the Internet goes
from the source to an ISP, into the cloud, out of the cloud to another ISP, and to its destination
How can the government control speech on the Internet? correct answers1) It can try to control the
speaker or the speaker's ISP, by criminalizing certain kinds of speech. But that won't work if the speaker
isn't in the same country as the listener.
2)It can try to control the listener, by prohibiting possession of certain kinds of materials. In the U.S.,
possession of copyrighted software without an appropriate license is illegal, as is possession of other
copyrighted material with the intent to profit from redistributing it.
3) The government can try to control the intermediaries.
How can Internet posters evaded being convicted for defamation/slander on the Web? correct
answersThe posters could evade responsibility as long as they remained anonymous, as they easily could
on the Internet.
What has Congress given ISPs relating to an Internet Defamation case? correct answersCongress had
given the ISPs a complete waiver of responsibility for the consequences of false and damag- ing
statements, even when the ISP knew they were false.
Internet Protocol Hourglass correct answersEach protocol interfaces only to those in the layers
immediately above and below it, and all data is turned into IP bit packets in order to pass from an
application to one of the physical media that make up the network.
-Email, Web, Phone
-SMTP, HTTP
-TCP, UDP
