what happens when we "do math" on a JavaScript object?

using the spread operator with two objects

checking the validity of JavaScript types with this library

rendering HTML within JavaScript functions

starting a React app without create-react-app

freezing objects to make them

using optional shorthand ways to write if/else statements

using optional shorthand ways to write if/else statements

concatenating strings with variables in a neater arrangement

employing special workarounds for special cases of strings

using other people's data sets with this function

delaying and repeating events based on time

accessing the HTML via JavaScript

more about JavaScript with the "user agent"

reviewing this calculation-oriented built-in object

reviewing this calendar-oriented built-in object

making changes to the HTML with JavaScript

responding to unsatisfactory data and actions

containing chunks of code for later re-use

performing more powerful functions such as transforming and filtering arrays

collecting several items in one container

collecting properties and values into containers

grouping code into actionable chunks

making events happen again and again

making decisions with if and else statements

reviewing essential math + logic + beyond

differentiating const + let + var when declaring variables

storing data into named containers

looking at and manipulating numbers in JavaScript

looking at and manipulating plain text in JavaScript