Back to the Basics…
If This, Then That
By the Numbers (and Letters)
Object-ively Speaking
Function Junction
200

This keyword allows a variable to be reassigned but not redeclared in the same scope.

What is let?

200

This operator checks if two values are equal in both value and type.

What is === (strict equality)?

200

This is returned by "hello"[1]

What is "e"?

200

This notation is required when the property name is stored in a variable.

What is bracket notation?

200

This will be returned: 

What is 5?

400

This happens when you declare a variable without assigning it a value, then log it.

What is undefined?

400

This will be the result of the expression: 5 > 3 && 2 > 4

What is false?

400

This will be logged: 

What is [1, 10, 3]?

400

This will be logged:

 

What is Ava?

400

This will be returned:

What is "negative"?

600

This term describes storing one variable’s value inside another variable.

What is assignment (assigning one variable to another)?

600

This structure is often used instead of multiple if-else statements for cleaner branching.

What is a switch statement?

600

This explains why you cannot directly change a character in a string.

What is string immutability?

600

This notation must be used if a property name contains a space.

What is bracket notation?

600

This pattern stops a function early when a condition is met.

What is the return early pattern?

800

This type of number can lead to precision issues like 0.1 + 0.2 !== 0.3.

What is a floating-point (decimal) number?

800

This will be logged:

What is true?

800

This will be logged

What is 3?

800

This will be logged:

What is 28?

800

This will be returned:

What is false?

1000

This method is commonly used to format a number to a fixed number of decimal places and returns a string.

What is .toFixed()?

1000

This concept explains why "10" == 10 evaluates to true.

What is type coercion?

1000

This method adds an element to the beginning of an array.

What is unshift()?

1000

This JavaScript keyword removes a property from an object.

What is delete?

1000

This will be returned:

What is 5?