Number

Question 1

What is _?

Answer 1

Numeric separator. Only for readability purposes.

Question 2

What is Number.parseInt()

Answer 2

Static method. Analyzes a string argument and returns an integer of the base specified. If the base is not specified, the default is 10. It is the same as the global function parseInt()

Question 3

What is NaN?

Answer 3

Is a value representing Not-A-Number. It is a property of the global object.

Question 4

What operations return NaN?

Answer 4

1. Failed number conversions
2. Math operations where the result is not a real number
3. Indeterminate form
4. A method or expression whose operand is or gets coerced to NaN. NaN is contagious.
5. Other cases where an invalid value is to be represented as a number.

Question 5

What is the % operator?

Answer 5

Division remainder. Returns the remainder left over when one operand is divided by a second operand. It always takes the sign of the dividend.