CS Section 6 - Design, Testing and IDEs

• What is the purpose of Defensive Design in programming?

  To ensure programs function properly
• Why do even the biggest software companies need to update their programs regularly?

  Because programs can have errors that need fixing
• How can programmers protect their programs through Defensive Design?

  By anticipating user misuse and preventing it
• What are the two main methods to prevent users from entering unwanted data?

  Input sanitisation and input validation
• What is input sanitisation?

  Removing unwanted characters before passing data through the program
• What is input validation?

  Checking if data meets certain criteria before passing it into the program
• Give an example of input validation.

  Checking that an email address contains an @ symbol
• What are the types of input validation checks?

  • Range check
  • Presence check
  • Check digit (CD)
  • Formal check
  • Look-up table
  • Length check
• What does a range check do?

  Checks the data is within a specified range
• What does a presence check do?

  Checks the data has actually been entered
• What does a check digit (CD) do?

  Checks numerical data has been entered accurately
• What does a formal check do?

  Checks the data has the correct format
• What does a look-up table do?

  Checks the data against a table of acceptable values
• What does a length check do?

  Checks the data is the correct length
• What does the function formatName() do?

  It removes unwanted characters from a string
• Is the function formatName() an example of input sanitisation or input validation?

  It is an example of input sanitisation
• What are two validation checks Karen could use for a file name?

  Presence check and length check
• Why is authentication important in programming?

  It confirms the identity of a user before accessing data
• How do passwords typically work in authentication?

  They are associated with a username to verify identity
• What is one way to increase password security?

  Force users to use strong passwords
• What is a feature of well-maintained code?

  It includes comments explaining key features
• Why is indentation important in programming?

  It helps to separate different statements for clarity
• What should variable names in code refer to?

  What they actually are to help programmers understand
• When should testing be conducted in the software development cycle?

  Before the program is released
• What are the two types of programming errors?

  Syntax errors and logic errors
• What is a syntax error?

  When the compiler doesn't understand the code due to incorrect grammar
• What is a logic error?

  When the program runs but does something unexpected
• How can syntax errors be diagnosed?

  By compilers and interpreters that return error locations
• How are logic errors typically found?

  Through general use of the program and systematic testing
• What is functionality testing?

  Testing to see if the program meets initial requirements
• Why shouldn't functionality testing be left until the end of the process?

  Because it's better to spot errors early during development
• What are the different types of testing in programming?

  • Performance Test: Tests speed and resource impact
  • Usability Test: Tests user-friendliness
  • Security Test: Tests vulnerability and data security
  • Load/Stress Test: Tests performance under extreme conditions
• What is the purpose of a flow diagram in software design?

  To outline the requirements and design of the program
• What are high-level programming languages?

  Languages that are easy for humans to write
• What are low-level programming languages?

  Languages that are easier for computers to run but tricky for humans
• What is machine code?

  The binary code that computers can read and execute
• What is assembly language?

  A low-level programming language that is easier for humans than machine code
• Why are high-level languages popular with programmers?

  Because they are easier for humans to write
• What is the purpose of testing in software development?

  Testing ensures that the software meets its requirements and functions correctly.
• What are the two types of computer languages?

  • High-Level Languages
  • Low-Level Languages