\s, which is a lowercase s. This pattern not only matches whitespace, but also carriage return, tab, form feed, and new line characters. You can think of it as similar to the character class [ \r\t\f\n\v].
```js
let whiteSpace = "Whitespace. Whitespace everywhere!"
let spaceRegex = /\s/g;
whiteSpace.match(spaceRegex);
// Returns [" ", " "]
```
countWhiteSpace to look for multiple whitespace characters in a string.
\s to match all whitespace characters.
    testString: assert(/\\s/.test(countWhiteSpace.source));
  - text: Your regex should find eight spaces in "Men are from Mars and women are from Venus."
    testString: assert("Men are from Mars and women are from Venus.".match(countWhiteSpace).length == 8);
  - text: 'Your regex should find three spaces in "Space: the final frontier."'
    testString: 'assert("Space: the final frontier.".match(countWhiteSpace).length == 3);'
  - text: Your regex should find no spaces in "MindYourPersonalSpace"
    testString: assert("MindYourPersonalSpace".match(countWhiteSpace) == null);
```