JavaScript Crash Course

• What is HTML?
• What is CSS?
• What is JavaScript?
• What can I do with them?

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What can I do with JavaScript?

Basic Syntax

Simple Types -- single, atomic values

• null -- Intentionally Empty
• Boolean -- Yes or No, there is no Maybe
• Number -- Everything has a decimal point, whether you want it or not.
  • integer math can be screwy
  • computers are bad at fractional numbers
• String -- Any text, delimited by single- or double-quotes
  • can be "added" together via concatenation
  • modifying produces a different value

Container Types -- collections

• Array -- a numbered list of "elements" or "items"
  • all elements have a corresponding Number called an "index"
  • element numbering is automatic and starts with 0
  • internally track the number of items: the "length" of the list
  • allows items to be added and removed via special action words: "methods"
  • allows access to each item via square brackets: list[index]
• Object -- a dictionary of "keys" mapped to "values"
  • every key is always a String in JavaScript
  • allows access to each value via dot notation: dictionary.key

It's Complicated...

• Function -- a snippet of code to run later
  • optionally accepts a list of inputs: "parameters" or "arguments"
  • always provides an output via a return statement, undefined otherwise
  • optionally produces side-effects by altering its "scope"