The Modern JavaScript Bootcamp (2019) - More on Variables

The video tutorial covers the basics of variables in JavaScript, including how to define and reassign them. It explains the rules for naming variables, such as starting with a letter or specific symbols, and avoiding reserved keywords. The tutorial also demonstrates common errors and how to resolve them, providing a foundational understanding of variable management in JavaScript.

What happens if you try to define a variable with the same name twice using 'let' in JavaScript?

• JavaScript throws a syntax error.

• The second variable is ignored.

• The variable is overwritten without any error.

• The program runs but with unexpected results.

Which of the following is a valid variable name in JavaScript?

• 1variable

• variable$

• variable#

• variable!

Why can't a variable name start with a number in JavaScript?

• It makes the code run slower.

• It is reserved for special functions.

• It is allowed, but not recommended.

• It causes a syntax error.

Which character is NOT allowed as the first character in a JavaScript variable name?

• An exclamation mark (!)

• A letter

• An underscore (_)

• A dollar sign ($)

What is a reserved keyword in JavaScript?

• A word that is ignored by the compiler.

• A word that is used for comments.

• A word that has a special meaning in the language.

• A word that can be used as a variable name.

Which of the following is a reserved keyword in JavaScript?

• var

• let

• const

• function

How can you avoid using a reserved keyword as a variable name?

• By adding a number at the end.

• By using it in uppercase.

• By using it in lowercase.

• By slightly altering the keyword.