BIG IDEA 1: CREATIVE DEVELOPMENT · CHEAT SHEET
Creative Development — the one-page version
Every key term and every exam tip from the 4 topics in this big idea. Print it, fold it, read it on the bus.
1.1Collaboration
- Pair programming
- two programmers share one workstation; one writes (driver) while the other reviews (navigator), switching regularly
- Collaboration
- working together throughout development to combine perspectives and skills
Tip: When a question asks why collaboration helped, the correct option almost always mentions diverse perspectives, reduced bias, or catching errors earlier. Options claiming collaboration makes programs run faster or use less memory are distractors — collaboration is about the people process, not program performance.
1.2Program Function and Purpose
- Program
- a collection of statements a computer executes to accomplish a task
- Input
- data a program receives from a user, file, sensor, or another program
- Output
- data or behavior a program produces, such as text, graphics, or audio
- Event
- an action, such as a click or key press, that triggers a program response
- Code segment
- a portion of a program's code
Tip: The Create Task written response asks you to state your program's purpose and its function separately. Purpose = the human problem it addresses. Function = the behavior when it runs. Practice writing both in one sentence each for any program you look at.
1.3Program Design and Development
- Iterative development
- repeatedly cycling through design, build, and test phases to refine a program
- Incremental development
- building a program in small pieces, testing each before adding the next
- Prototype
- an early, partial version of a program used to test ideas
- Documentation
- written descriptions and comments that explain what a program does and how it works
- Comment
- a note inside code intended for humans and ignored by the computer
- Requirements
- a description of what a program must do, often gathered from users
Tip: If a question describes a team that repeatedly revisits earlier phases after testing, the answer is iterative. If it describes adding features one working piece at a time, the answer is incremental. They often happen together, but the exam tests them as separate terms.
1.4Identifying and Correcting Errors
- Syntax error
- a mistake in the code's structure that prevents it from running
- Logic error
- a mistake in the algorithm that produces incorrect output while the program still runs
- Run-time error
- an error that occurs during execution and stops the program
- Overflow error
- a result too large to be represented in the available bits
- Round-off error
- an error from real numbers that cannot be represented exactly in binary
- Hand-tracing
- stepping through code manually, tracking each variable's value
- Debugging
- finding and fixing errors in a program
Tip: Classify by symptom. Won't run at all → syntax. Runs, then crashes partway → run-time. Runs to the end with the wrong answer → logic. Result is a nonsense huge/tiny number → overflow. The exam rarely asks you to name the error type without giving you one of these symptoms.