Objects

When to use Object

• When yu don't need ordering
• When you need fast access / insertion and removal.

Big O of Objects

• Insertion - 0(1)
• Removal - 0(1)
• Searching - 0(N)
• Accessing - 0(1)

let instructor = {
    firstName: "kelly",
    isInstructor: true,
    favoriteNumber: [1,2,3,4]
}

Big O of Objects Methods

• Object.keys - 0(n)
• Object.values - 0(N)
• Object.entries - 0(N)
• hasOwnProperty - 0(1)

Arrays

• Ordered lists but the order cames at a cost for some of the operations (insertion & removal)
• access with index is 0(1) operation

Methods

• Insertion (end) - push - 0(1)
• Insertion (begining) & Removing form begining - 0(n)
  • we need re-index all other elements.
• Searching - 0(N)
• Accessing - 0(1)

Array methods

• push - 0(1)
• pop - 0(1)
• shift - 0(N)
• unshift - 0(N)
• concat - 0(n)
• slice - O(n)
• splice - 0(n)
• sort - 0(n)
• forEach/map/filter/reduce/etc. - 0(n)