Making Machines Understand: teacher key

How Coding Works, grade 8 edition, written for 8th grade. Code, algorithms and bugs: Euclid, Ada Lovelace, Grace Hopper, FORTRAN, COBOL, JavaScript and the Hour of Code.

Read the book. Print this page for the key.

Questions and answers

1. About when did Euclid's Elements contain an algorithm for the greatest common divisor?
   • About 300 BCE (answer)
   • In 1843
   • In 1957
2. What did Ada Lovelace's 1843 notes describe?
   • How to build a compiler
   • How the Analytical Engine could be programmed to compute Bernoulli numbers (answer)
   • How to write the first computer manual
3. What did Grace Hopper's 1957 division develop?
   • Flow-Matic (answer)
   • FORTRAN
   • The Mark I
4. What is the job of semantics?
   • Making sure instructions are meaningful (answer)
   • Setting the order of code
   • Running the code line by line
5. In the page about debugging, what does a debugger let programmers do?
   • Step through code a line at a time (answer)
   • Rename a language
   • Build a web page
6. Why can code in one browser tab not directly affect code in another tab?
   • Each tab runs in its own separate environment (answer)
   • JavaScript only runs on one page
   • Tabs share one API

Words

• algorithm: list of steps
• compiler: code translator
• syntax: code writing rules
• semantics: meaning
• debugger: bug-finding tool