AP COMPUTER SCIENCE PRINCIPLES EXAM COMPLETE STUDY GUIDE
FOR 2022 A NEW SOLUTION
Overflow - error that results when the number of bits is not enough to hold the number, like a
car's odometer "rolling over"
Round-off - error 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 - Compressing data in a way that throws some data away and makes it almost impossible
to recover the original, great compression, like JPEG images
Lossless - Compressing 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 - data about data, like a camera storing the location, aperture, shutter speed, etc. for
a digital photo
Sequencing - code flows line by line, one after another, like a recipe
Selection - a boolean condition to determine which of two algorithmic paths are taken, aka if-
then
Iteration - using a looping control structure, like while, for, foreach, repeat, repeat-until, etc.
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, like doubling every time your
input grows by one
Heuristic - using a "rule" to guide an algorithm, like always walking toward the north star if you
were stuck in a forest
Undecidable - A 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 - Going one by one vs starting in the middle and going left/right like looking for a
word in the dictionary
Binary Search - requires the list to be sorted in order and then cutting the list in half
, APIs - Application Programming Interface
Citizen Science - Lots of people to help with a scientific project, like asking everyone around the
world to count the butterflies they see one day
Cloud Computing - Using distributed calculations and/or storage for big data or a web
application
Crowdsourcing - Asking lots of users online to help with something, like funding a project, or
running SETI@Home to help look for extraterrestrial signals
Creative Commons - An 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 - A policy that allows people to have read access to things, e.g., libraries or online
data
Moore's Law - The # of transistors on a chip doubles every two years
Peer-to-peer Networks - A 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 - The idea that some communities / populations have less access to computing
than others
ISP - Internet Service Provider
How does internet communication arrive at its destination? - Speech 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? - 1) 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? - The
posters could evade responsibility as long as they remained anonymous, as they easily could on
the Internet.
FOR 2022 A NEW SOLUTION
Overflow - error that results when the number of bits is not enough to hold the number, like a
car's odometer "rolling over"
Round-off - error 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 - Compressing data in a way that throws some data away and makes it almost impossible
to recover the original, great compression, like JPEG images
Lossless - Compressing 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 - data about data, like a camera storing the location, aperture, shutter speed, etc. for
a digital photo
Sequencing - code flows line by line, one after another, like a recipe
Selection - a boolean condition to determine which of two algorithmic paths are taken, aka if-
then
Iteration - using a looping control structure, like while, for, foreach, repeat, repeat-until, etc.
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, like doubling every time your
input grows by one
Heuristic - using a "rule" to guide an algorithm, like always walking toward the north star if you
were stuck in a forest
Undecidable - A 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 - Going one by one vs starting in the middle and going left/right like looking for a
word in the dictionary
Binary Search - requires the list to be sorted in order and then cutting the list in half
, APIs - Application Programming Interface
Citizen Science - Lots of people to help with a scientific project, like asking everyone around the
world to count the butterflies they see one day
Cloud Computing - Using distributed calculations and/or storage for big data or a web
application
Crowdsourcing - Asking lots of users online to help with something, like funding a project, or
running SETI@Home to help look for extraterrestrial signals
Creative Commons - An 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 - A policy that allows people to have read access to things, e.g., libraries or online
data
Moore's Law - The # of transistors on a chip doubles every two years
Peer-to-peer Networks - A 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 - The idea that some communities / populations have less access to computing
than others
ISP - Internet Service Provider
How does internet communication arrive at its destination? - Speech 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? - 1) 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? - The
posters could evade responsibility as long as they remained anonymous, as they easily could on
the Internet.
