JS primitives and variables

Question 1

What is the purpose of variables?

Answer 1

store bits of information/store data to be used in the future

Question 2

How do you declare a variable?

Answer 2

variable keyword and name of variable

ex) var fullName

Question 3

How do you initialize (assign a value to) a variable?

Answer 3

equal sign 
ex) var fullName = 'Marley Doughty'

Question 4

What characters are allowed in variable names?

Answer 4

letters, $, underscore_, numbers (but CANNOT start with number)

Question 5

What does it mean to say that variable names are “case sensitive”?

Answer 5

uppercase and lowercase are treated as separate entities

ex) fullName !== FullName

Question 6

What is the purpose of a string?

Answer 6

storing and manipulating text

Question 7

What is the purpose of a number?

Answer 7

math- determine quantities, dimensions, time

Question 8

What is the purpose of a boolean?

Answer 8

determine if a value is true or false

Question 9

What does the = operator mean in JavaScript?

Answer 9

assignment operator, assigns value to a variable

Question 10

How do you update the value of a variable?

Answer 10

variable name then assign new value
ex) var totalPets = 2; (new value is 3 pets)
totalPets += 1;

Question 11

What is the difference between null and undefined?

Answer 11

null is intentional absence like a placeholder meaning no value, whereas undefined is an absence of a value , no value has been assigned or the variable has not been declared

Question 12

Why is it a good habit to include “labels” when you log values to the browser console?

Answer 12

adds a message in the log that helps maintain organization of variable values, reminds you where it came from (easier to debug)

Question 13

Give five examples of JavaScript primitives.

Answer 13

string, number, boolean, undefined, null