Advanced Array Method Recap

forEach

: iterates over an array, runs a callback on each value and returns undefined

map

: creates a new array, runs a callback on each value and pushes the result of each callback in the new array

filter

: creates a new array, runs a callback on each value and if the result of the callback returns true, that value is added to the new array

some

: iterates through an array and runs a callback on each value, if the callback for at least one value returns true, some returns true, otherwise false

every 

: iterates through an array and runs a callback on each value, if the callback at any time returns false, every returns false

reduce

: returns an accumulated value which is determined by the result of what is returned to each callback