Intro to JavaScript

1. Which keywords are used to declare a variable in JavaScript?

Var Let and Const

2. What is the definition of a function?

Resuable set of statements to perform an action. 

3. What are the SOLID principles?

Single Responsibility, 
Open-closed principle,
liskov substitution principle,
interface segregation principle, and dependency inversion principle.

4. Given this array:

let fruit = ['apple', 'banana', 'pineapple',  'orange', 'strawberry']

What index is the pineapple's current position? How do you know?

The pineapple's current position is [2] because arrays are zero indexed. 

5. With these two objects:

let you = { name:"You", hair: true, friends: [] }
let them = { name:"Them", hair: false, friends: [] }

how would you .push the them object into the you object's array of friends?

you.push(them.name)

6. Give an example of a JavaScript Conditional:

if (10 < 12){
  console.log("10 is less than 12" )
} 

7. In the for loop below, what is the name of the piece belongs inside the empty "______" space? What would you put here to increase i by one on every iteration?

for ( let i = 0; i < arr.length; _______ ) {
  //...

i++

8. What does the DOM acronym stand for? Which file is first accessed to render the DOM?

Document Object Model. The first file to be accessed is the index.HTML file. 

9. What are the 9 ECMAScript types as defined by MDN?

 Numbers, Strings, Booleans, Undefined, Null, Symbol, objects, arrays, functions

10. When it comes to functions or methods, what is the difference between a parameter and an argument?

parameters are the variables you pass into a function while the argument is the action of the function. 

11. What is the difference between a primitive value and a reference value?

primitives store the actual value, while references store the route to the objects they refer to.