we learn plenty of new interest an arraya is a list of values that you should separate in comas inside of solit brakets. Arrays are simply store for multiple objects that can be organize in square brackets and can be aces in numerical index through the code. With the first item of the array starting at zero you can also create a loop.
Also we lear to add boolean to our code for true or false statements that can be interpret such as if this is true do this, this method could test a function and keep track of the process while addition or subtracting functions. in this example we can see that if the statement is true and the mouse will go in the middle of the rectangle the square will light a red color inside and if press the background will change to green.We can find more information on this site https://github.com/processing/p5.js/wiki/JavaScript-basics#data-type-boolean
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