Instructions a Machine Can Follow: teacher key

How Coding Works, grade 9 edition, written for 9th grade. Writing code means giving a computer precise, ordered instructions. Algorithms, binary, early languages, the building blocks of programs, Python, Scratch and bug-fixing are all part of it.

Read the book. Print this page for the key.

Questions and answers

1. What does a compiler do?
   • It translates a program into machine code the computer can run (answer)
   • It finds typing mistakes by itself
   • It makes a computer think for itself
2. Who is named as the person who coined the word compiler?
   • John Backus
   • Grace Hopper (answer)
   • Guido van Rossum
3. What does a loop do?
   • It makes a computer repeat a set of instructions (answer)
   • It turns code into binary
   • It holds a value that never changes
4. A program gives the wrong answer because its instructions are in the wrong order. Which kind of bug is that?
   • A syntax error
   • A logic error (answer)
   • A comment
5. Why can a variable keep track of a score?
   • Its value can change (answer)
   • It can only be true or false
   • It is written in machine code
6. In the passage, what does the word syntax mean?
   • The rules for how code must be written (answer)
   • A kind of computer hardware
   • A note the computer does not run

Words

• algorithm: step-by-step procedure
• compiler: code translator
• variable: value container
• debugging: fixing bugs
• syntax: writing rules