AP Computer Science Principles Exam Instructions

The 200-word examination instruction list

AP Computer Science Principles asks you to trace algorithms, explain abstractions and discuss computing effects. For written responses, answer about the program in your own Personalized Project Reference and point to the code behaviour the prompt asks about.

Start with the list or jump to exam requirements, worked examples, the Fencing Method or practice. The list combines task verbs with subject terms that help you interpret the question.

Essential instructions

No.	Instruction or term	Meaning or action
1	Identify	Name or pick out the item the question specifies.
2	State	Express the required point directly and clearly.
3	Describe	Report the relevant characteristics, events or pattern.
4	Explain	Connect the result to its cause, mechanism or reasoning.
5	Compare	Set the items side by side on the same relevant feature.
6	Interpret	Say what a statement, result or display means in context.
7	Justify	Give evidence for the claim and explain how that evidence supports, qualifies or defends it.
8	Evaluate	Weigh relevant evidence or criteria before reaching a judgment.
9	Determine	Work from the given information to establish an answer.
10	Calculate	Use numbers or other given information to work out a result.
11	Estimate	Find an approximate answer using the available clues.
12	Sketch	Show the required shape, relationships and labels.
13	Construct	Produce the specified representation using the information given.
14	Label	Attach the correct name to the indicated part.
15	Select	Choose only the number of options requested.
16	Check	Test the answer against the original instruction or condition.
17	Analyze	Break the information into relevant parts and explain how they relate.
18	Multiple-choice question	Select the answer that satisfies the full stem and any limiting words.
19	Free-response question	Produce your own answer and complete each labelled task.
20	Stimulus	Use the figure, extract or other material attached to the question.
21	Answer each subpart	Treat each lettered instruction as a separate job.
22	Fully digital	Complete both parts in Bluebook for the May 2027 AP Statistics exam.

Computing concepts and portfolio instructions

No.	Instruction or term	Meaning or action
23	Create performance task	Develop a program and submit the required code, video and Personalized Project Reference under current College Board rules.
24	Personalized Project Reference	Use the submitted code excerpts available during written response to answer about your own program.
25	Program purpose	State the user need, problem or creative goal addressed by the program.
26	Program functionality	Describe what the program actually does when it runs.
27	Program design	Explain how the code or interface supports the intended purpose.
28	Program input	Identify data received from a user, device, file or other source.
29	Program output	Identify information or behaviour the program produces.
30	Procedure call	Identify where the procedure is invoked and explain what arguments it receives.
31	Procedural abstraction	Give a named operation whose implementation details can be hidden from its callers.
32	Data abstraction	Represent data with a structure that can be used without tracking each low-level detail.
33	Manage complexity	Explain how an abstraction reduces duplicated work or makes the program easier to maintain or extend.
34	Algorithm	A finite sequence of steps for completing a task.
35	Sequencing	Carry out steps in the stated order.
36	Selection	Choose an action according to a condition.
37	Iteration	Repeat steps under the stated count or condition.
38	Assignment	Store an evaluated result in a variable.
39	Boolean value	A value that is either true or false.
40	List	An ordered collection of elements accessed according to the stated indexing convention.
41	One-based indexing	Start counting elements at position one when using the College Board exam reference notation.
42	Append	Add a new element to the end of a list.
43	Insert	Place an element at a specified position and account for shifting later positions.
44	Remove	Delete the specified list element and account for later elements shifting.
45	Repeat until	Continue while the condition is false and stop when it becomes true in the exam notation.
46	For each	Process the elements of a collection in the given traversal order.
47	Random integer	Use the range and endpoint rules stated in the reference notation.
48	Modulus	Find the remainder according to the operation’s definition.
49	Reasonable time	Distinguish algorithmic growth that is polynomial from growth treated as unreasonable in the course model.
50	Undecidable problem	A decision problem for which no algorithm always gives the correct yes-or-no answer for every valid input.
51	Heuristic	A practical strategy that can give a useful answer without guaranteeing the best solution.
52	Sequential computing	Carry out operations one after another.
53	Parallel computing	Carry out multiple operations at the same time when dependencies permit.
54	Distributed computing	Use multiple networked devices to perform parts of a computation.
55	Speedup	Compare sequential execution time with parallel execution time.
56	Simulation	Use a computational model to investigate behaviour under stated assumptions.
57	Model limitation	Identify a real-world factor the simulation simplifies or leaves out.
58	Binary representation	Encode information using two possible symbols, conventionally zero and one.
59	Bit	A single binary digit.
60	Byte	A group of eight bits.
61	Overflow	A computed value exceeds the representable range under a fixed representation.
62	Round-off error	A numerical difference caused by limited precision.
63	Lossless compression	Reduce data size while preserving the ability to recover the original exactly.
64	Lossy compression	Reduce data size by discarding information, so exact recovery is generally impossible.
65	Metadata	Data describing other data, such as its format or timestamp.
66	Data cleaning	Find and handle errors, inconsistencies or missing entries before analysis.
67	Crowdsourcing	Collect contributions from a broad group of people.
68	Citizen science	Involve members of the public in scientific data collection or analysis.
69	Computing innovation	A development with a program as an integral part of its function.
70	Packet	A unit of data transmitted through a network with relevant control information.
71	Routing	Choose paths for packets through a network.
72	Protocol	An agreed set of rules for communication.
73	IP address	Identify a network endpoint or interface for addressing and routing.
74	Domain Name System	Translate domain names into records such as IP addresses.
75	Fault tolerance	Keep a system operating when some components fail.
76	Redundancy	Use extra paths or components to support recovery or continued service.
77	Scalability	Maintain useful performance or service as the system grows.
78	Bandwidth	The rate at which a connection can transfer data under the stated definition.
79	Latency	The delay between sending and receiving or responding.
80	Encryption	Use a key and algorithm to transform readable data into protected form.
81	Public-key encryption	Use related public and private keys for tasks such as confidential communication.
82	Multifactor authentication	Require evidence from distinct authentication-factor categories.
83	Phishing	Use deceptive messages or sites to induce disclosure or another unsafe action.
84	Personally identifiable information	Information that can identify a person directly or when combined with other information.
85	Digital divide	Differences in access to computing, connectivity or the ability to use them effectively.
86	Computational bias	Systematic skew that can arise from data, design choices or deployment conditions.
87	Beneficial effect	Identify who benefits and explain how the computing innovation produces the benefit.
88	Harmful effect	Identify who is harmed and explain how the innovation contributes to that harm.
89	Intellectual property attribution	Credit borrowed material and follow the applicable course submission rules.
90	Single-select item	Choose one answer.
91	Multiple-select item	For the exam’s multiple-select items, choose two answers as instructed.
92	Test the procedure with a new input	State the input, trace the relevant branch or loop and give the expected behaviour.

Algorithm tracing and testing

No.	Instruction or term	Meaning or action
93	Implement	Write or express an algorithm that performs the task under the stated requirements.
94	Trace	Follow the code in execution order and record how values change.
95	Determine the output	Give exactly what the program prints, including order and spacing when relevant.
96	Return a value	Use return to hand the requested result back to the caller.
97	Modify in place	Change the existing object or collection while preserving its identity.
98	Do not modify the input	Keep the supplied data intact while producing the requested result.
99	Parameter	Identify a quantity that sets a feature of the model.
100	Argument	Identify the expression supplied at the call site.
101	Scope	The region where a name can be used.
102	Expression	A piece of code that evaluates to a value.
103	Statement	A complete assertion to examine or respond to.
104	Increment	Increase a value by one.
105	Decrement	Decrease a value by one.
106	Operator precedence	Determine which operator binds first when grouping is implicit.
107	Boolean expression	Evaluate the condition to true or false.
108	Comparison operator	Test a relation such as less than or equality.
109	Logical AND	Evaluate true only when both conditions are true.
110	Logical OR	Evaluate true when either or both conditions are true.
111	Logical NOT	Reverse a Boolean value.
112	Branch	Select a code path based on a condition.
113	Nested conditional	A conditional statement inside another conditional’s branch.
114	Loop guard	The condition tested to decide whether a loop continues.
115	Loop update	The change made to control state between iterations.
116	Nested loop	A loop inside the body of another loop.
117	Traversal	Visit the required elements in the order the task specifies.
118	Accumulator	A variable updated to build a running result.
119	Counter	A variable that tracks how often an event occurs.
120	Sentinel value	A designated value used to signal a boundary or stopping condition.
121	Off-by-one error	An index or count mistake caused by moving a boundary one position.
122	Bounds check	Confirm an index is at least zero and smaller than the structure’s length or size.
123	String concatenation	Join text using + and check the grouping when numbers are present.
124	Lexicographic order	Compare text using the ordering defined by the applicable comparison method.
125	Side effect	An observable change, such as updating a field or printing, beyond returning a value.
126	Precondition	A requirement callers may be expected to satisfy before the operation.
127	Postcondition	A result or state change the operation must guarantee afterward.
128	Edge case	An input at or near a boundary that may behave differently.
129	Test case	A specific input and expected result used to check the specification.
130	Dry run	Walk through the code by hand with concrete inputs.
131	Logic error	Code runs but yields an incorrect result for the intended task.
132	Linear search	Check elements in order until the desired result is found or the search ends.
133	Binary search	Narrow the range repeatedly in data sorted by the relevant ordering.
134	Visit once	Process every required element exactly one time.
135	Preserve order	Keep the relative sequence of items that remain or are returned.
136	Empty list	A list with size zero.
137	Empty string	A String whose length is zero.
138	First match	The earliest eligible element in the required traversal order.
139	Last match	The final eligible element in the required traversal order.
140	Duplicate	An additional occurrence of a value already present under the stated equality rule.
141	Consecutive	Adjacent in the order being examined.
142	Minimum	The smallest eligible value under the specified comparison.
143	Maximum	The largest eligible value under the specified comparison.
144	Tie	A case where competing values have the same ranking.
145	Integer overflow	A fixed-width integer operation produces a value outside its representable range and can wrap.
146	Boolean flag	A variable that stores whether a condition has been met.
147	Loop invariant	A property that stays true at a designated point in each iteration.
148	Exit condition	The condition under which repetition stops.
149	Return early	Finish the method as soon as the required result is known and doing so preserves the contract.
150	Combine conditions	Use the appropriate Boolean operations and grouping to express the full requirement.
151	Sample output	The exact result shown for an example input.
152	Test the smallest allowed case	Use the minimum input size permitted by the specification.
153	Random value	A value generated within the range specified by the operation.
154	Index shift	Recalculate which position an element occupies after an insertion or removal.
155	Temporary variable	Store an intermediate value for use in a later expression or operation.
156	Swap	Exchange two values without losing either original value.
157	Input guarantee	A property the prompt promises, such as all array entries being non-null.

Evidence and other exam wording

No.	Instruction or term	Meaning or action
158	Contrast	Show how the items differ on a shared point of comparison.
159	Infer	Use clues to reach a conclusion the material implies.
160	Predict	Use available evidence to say what is likely to happen.
161	Suggest	Offer a plausible answer suited to the information given.
162	Assess	Judge the extent, value or strength of something using evidence.
163	Discuss	Develop a structured response that considers the relevant issues.
164	Distinguish	Give the feature that lets the reader tell two things apart.
165	Support	Supply evidence that helps establish the claim.
166	Illustrate	Make an idea clear with a relevant example or diagram.
167	Demonstrate	Show how a fact, process or result can be established.
168	Arrange	Put items into the order or grouping requested.
169	Sequence	Put stages into a meaningful order.
170	Classify	Assign each item to a category using the stated rule.
171	Order	Sort items by the criterion given in the prompt.
172	Omit	Leave out the indicated item or detail.
173	Include	Make sure the requested part appears in the response.
174	Exclude	Keep the named item or category outside your answer.
175	Refer to	Use the specified passage, figure or notes when responding.
176	Based on	Ground the answer in the material named in the question.
177	According to	Use what the specified source says.
178	In context	Use the meaning that fits this passage or situation.
179	Most likely	Choose the conclusion with the strongest support among the options.
180	Best supported	Prefer the conclusion backed most directly by the evidence.
181	Explicit	Stated directly in the source.
182	Implicit	Suggested by the source and recoverable from clues.
183	Evidence	A fact, detail or observation that supports a claim.
184	Claim	An assertion that can be tested against evidence or reasoning.
185	Example	A particular case used to make a general idea clear.
186	Conclusion	The result reached after considering the reasoning or evidence.
187	Assumption	A premise taken as given for the purpose of the question.
188	Condition	A requirement that must be satisfied.
189	Constraint	A restriction that shapes the possible answers.
190	Criterion	A standard used to choose or judge an answer.
191	Context	The surrounding information that helps determine meaning.
192	Source	The particular text, figure, notes or data supplied for use.
193	Passage	A stretch of text provided for reading and answering questions.
194	Option	One of the choices the question offers.
195	Section	A group of questions or tasks within a test.
196	Figure	A numbered graph, image or diagram referred to in the task.
197	Table	Information arranged in rows and columns.
198	Graph	A visual display of data or a mathematical relationship.
199	Diagram	A drawing showing features, structure or relationships.
200	Trend	The broad direction or pattern over a range.

What the AP Computer Science Principles exam requires

College Board lists the regular 2027 exam for May 14. The end-of-course exam is fully digital. You select answers and type responses in Bluebook.

Exam component	Format and weighting
Multiple choice	70 questions in 120 minutes, worth 70%. The section includes single-select questions, questions about a computing innovation and items that require two selections.
Create and written response	Together worth 30%. The portfolio has program code, a video and the Personalized Project Reference. The Bluebook written section lasts 60 minutes and presents two questions with four prompts in total.
Portfolio deadline	April 30, 2027, at 11:59 p.m. U.S. Eastern Time. Submit the three components as final in the AP Digital Portfolio.
Calculator policy	Calculators are prohibited unless a student has an approved four-function calculator accommodation.

College Board specifies nine hours of in-class time for Create. The written prompts cover program design, function and purpose, algorithm development, errors and testing, and data and procedural abstraction. The Personalized Project Reference is available during that section.

AP is a U.S.-based programme taken domestically and internationally. Confirm local reporting time and registration with your school or test centre. Practise with the official materials for your course and exam year.

Read the task before choosing a method

Review the reference notation used in multiple choice, including list indexing and loop behaviour. For the written section, practise using your own submitted excerpts to explain what the program does, why an algorithm works and which input tests a particular case.

Worked examples for common exam instructions

Trace a list algorithm

Prompt. A list contains [2, 5, 8]. The algorithm starts total at zero and adds each element only if it is greater than 4. What is the result?

Answer. The algorithm skips 2 and adds 5 and 8. The final total is 13.

Explain how data abstraction manages complexity

Prompt. A program keeps all scores in one list rather than in separately named variables. Explain one benefit.

Answer. One loop can process every score using the same instructions. Adding another score requires adding an element rather than adding a variable and another calculation step.

Design a boundary test

Prompt. A procedure labels a score of 60 or more as passing. Give two inputs and expected outputs that test the threshold.

Answer. Input 59 should produce a failing label and input 60 should produce a passing label. The pair tests both sides of the comparison and checks whether the boundary is included.

Explain a computing trade-off

Prompt. A public transit app collects precise location to give arrival alerts. Describe one benefit and one potential harm.

Answer. Precise location can help notify riders when they approach a stop. If precise location records are retained or exposed, they may reveal individuals’ routines. These are distinct consequences of the same data collection.

Use the Fencing Method to build an answer

Start with a small, accurate response. Add the detail that fixes it to the question, then add the reason that connects them. Test the explanation on a new case.

Start. The procedure finds matches.

Add context. The procedure checks each list item against the search value supplied as its parameter.

Add reasoning. Each comparison can add one item to the results. The same procedure works for a different search value because that value is passed as an argument.

Transfer. Choose a new input that gives no matches and trace what is returned.

Practise with the 200 terms

Choose one algorithm trace, one test case and one explanation of abstraction. In the explanation, point to an operation in the code and describe what it lets the program do. Try the trace again with a boundary input.

Read the indexing rule

Try it. In the College Board notation, what is the first item in [7, 9, 12]?

Check. The first item is 7 at index 1. Use the notation specified by the question.

Frequently asked questions

Should my written answer use the exam pseudocode or my project language?

For the written responses, explain the behaviour of the code in your own project reference using the terminology the prompt calls for. In a multiple-choice trace, follow the notation and conventions supplied in the question and reference materials.

Official sources and next reading

College Board AP Computer Science Principles exam information and released questions · AP calculator policy · 2027 AP exam schedule

Top 200 Vocabulary Word List for AP Computer Science Principles | Must Know Words for Common Examination Instructions