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What does (upper) mean and do?

In this video the code after "function randomNumber" there is (upper). What is (upper) and what does it do?

function randomNumber(upper) { return Math.floor( Math.random() * upper ) + 1; } var counter = 0; while ( counter < 10 ) { var randNum = randomNumber(6); document.write(randNum + ' '); counter += 1; }

1 Answer

It is the argument that is passed in to the function. For this function, it would return a number between 1 and whatever you pass into the randomUpper function. The program calls the randomUpper function by passing in the number, 6. The variable, upper, contains the value 6 and the function returns a random number between 1 and 6.